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f7b47737 | 1 | Guile NEWS --- history of user-visible changes. -*- text -*- |
d23bbf3e | 2 | Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc. |
5c54da76 JB |
3 | See the end for copying conditions. |
4 | ||
e1b6c710 | 5 | Please send Guile bug reports to bug-guile@gnu.org. |
5c54da76 | 6 | \f |
f3227c7a JB |
7 | Changes since Guile 1.3: |
8 | ||
e4eae9b1 MD |
9 | * Changes to the stand-alone interpreter |
10 | ||
b3a941b9 MD |
11 | ** New options interface: readline-options, |
12 | readline-enable, readline-disable, readline-set! | |
13 | ||
e4eae9b1 MD |
14 | ** Command line history is now restored from and saved to file |
15 | ||
b3a941b9 MD |
16 | If readline is used and the readline option `history-file' is enabled, |
17 | the command line history is read from file when the interpreter is | |
e4eae9b1 MD |
18 | entered, and written to file on exit. The filename used can be |
19 | specified with the environment variable GUILE_HISTORY. Default file | |
20 | name is "$HOME/.guile_history". Nothing special happens if errors | |
21 | occur during read or write. | |
22 | ||
23 | ** Command line history length can now be customized. | |
b3a941b9 | 24 | Command line history length is now controlled by the readline option |
e4eae9b1 MD |
25 | `history-length'. Default is 200 lines. |
26 | ||
29672a5c MD |
27 | ** All builtins now print as primitives. |
28 | Previously builtin procedures not belonging to the fundamental subr | |
29 | types printed as #<compiled closure #<primitive-procedure gsubr-apply>>. | |
30 | Now, they print as #<primitive-procedure NAME>. | |
31 | ||
32 | ** Backtraces slightly more intelligible. | |
33 | gsubr-apply and macro transformer application frames no longer appear | |
34 | in backtraces. | |
35 | ||
55254a6a MD |
36 | * Changes to Scheme functions and syntax |
37 | ||
88ceea5c MD |
38 | ** New functions: delq1!, delv1!, delete1! |
39 | These procedures behave similar to delq! and friends but delete only | |
40 | one object if at all. | |
41 | ||
55254a6a MD |
42 | ** New function: unread-string STRING PORT |
43 | Unread STRING to PORT, that is, push it back onto the port so that | |
44 | next read operation will work on the pushed back characters. | |
45 | ||
46 | ** unread-char can now be called multiple times | |
47 | If unread-char is called multiple times, the unread characters will be | |
48 | read again in last-in first-out order. | |
49 | ||
d41b3904 MD |
50 | ** New function: serial-map PROC LIST1 LIST2 ... |
51 | Version of `map' which guarantees that the procedure is applied to the | |
52 | lists in serial order. | |
53 | ||
54 | ** New syntax: sequence->list BODY1 ... | |
55 | Version of `begin' which returns a list of the results of the body | |
56 | forms instead of the result of the last body form. In contrast to | |
57 | `begin', sequence->list allows an empty body. | |
58 | ||
e4eae9b1 MD |
59 | ** New functions: read-history FILENAME, write-history FILENAME |
60 | Read/write command line history from/to file. Returns #t on success | |
61 | and #f if an error occured. | |
62 | ||
3ffc7a36 MD |
63 | * Changes to the gh_ interface |
64 | ||
65 | ** gh_scm2doubles | |
66 | ||
67 | Now takes a second argument which is the result array. If this | |
68 | pointer is NULL, a new array is malloced (the old behaviour). | |
69 | ||
70 | ** gh_chars2byvect, gh_shorts2svect, gh_floats2fvect, gh_scm2chars, | |
71 | gh_scm2shorts, gh_scm2longs, gh_scm2floats | |
72 | ||
73 | New functions. | |
74 | ||
f3227c7a | 75 | \f |
d23bbf3e | 76 | Changes in Guile 1.3 (released Monday, October 19, 1998): |
c484bf7f JB |
77 | |
78 | * Changes to the distribution | |
79 | ||
e2d6569c JB |
80 | ** We renamed the SCHEME_LOAD_PATH environment variable to GUILE_LOAD_PATH. |
81 | To avoid conflicts, programs should name environment variables after | |
82 | themselves, except when there's a common practice establishing some | |
83 | other convention. | |
84 | ||
85 | For now, Guile supports both GUILE_LOAD_PATH and SCHEME_LOAD_PATH, | |
86 | giving the former precedence, and printing a warning message if the | |
87 | latter is set. Guile 1.4 will not recognize SCHEME_LOAD_PATH at all. | |
88 | ||
89 | ** The header files related to multi-byte characters have been removed. | |
90 | They were: libguile/extchrs.h and libguile/mbstrings.h. Any C code | |
91 | which referred to these explicitly will probably need to be rewritten, | |
92 | since the support for the variant string types has been removed; see | |
93 | below. | |
94 | ||
95 | ** The header files append.h and sequences.h have been removed. These | |
96 | files implemented non-R4RS operations which would encourage | |
97 | non-portable programming style and less easy-to-read code. | |
3a97e020 | 98 | |
c484bf7f JB |
99 | * Changes to the stand-alone interpreter |
100 | ||
2e368582 | 101 | ** New procedures have been added to implement a "batch mode": |
ec4ab4fd | 102 | |
2e368582 | 103 | *** Function: batch-mode? |
ec4ab4fd GH |
104 | |
105 | Returns a boolean indicating whether the interpreter is in batch | |
106 | mode. | |
107 | ||
2e368582 | 108 | *** Function: set-batch-mode?! ARG |
ec4ab4fd GH |
109 | |
110 | If ARG is true, switches the interpreter to batch mode. The `#f' | |
111 | case has not been implemented. | |
112 | ||
2e368582 JB |
113 | ** Guile now provides full command-line editing, when run interactively. |
114 | To use this feature, you must have the readline library installed. | |
115 | The Guile build process will notice it, and automatically include | |
116 | support for it. | |
117 | ||
118 | The readline library is available via anonymous FTP from any GNU | |
119 | mirror site; the canonical location is "ftp://prep.ai.mit.edu/pub/gnu". | |
120 | ||
a5d6d578 MD |
121 | ** the-last-stack is now a fluid. |
122 | ||
c484bf7f JB |
123 | * Changes to the procedure for linking libguile with your programs |
124 | ||
71f20534 | 125 | ** You can now use the `guile-config' utility to build programs that use Guile. |
2e368582 | 126 | |
2adfe1c0 | 127 | Guile now includes a command-line utility called `guile-config', which |
71f20534 JB |
128 | can provide information about how to compile and link programs that |
129 | use Guile. | |
130 | ||
131 | *** `guile-config compile' prints any C compiler flags needed to use Guile. | |
132 | You should include this command's output on the command line you use | |
133 | to compile C or C++ code that #includes the Guile header files. It's | |
134 | usually just a `-I' flag to help the compiler find the Guile headers. | |
135 | ||
136 | ||
137 | *** `guile-config link' prints any linker flags necessary to link with Guile. | |
8aa5c148 | 138 | |
71f20534 | 139 | This command writes to its standard output a list of flags which you |
8aa5c148 JB |
140 | must pass to the linker to link your code against the Guile library. |
141 | The flags include '-lguile' itself, any other libraries the Guile | |
142 | library depends upon, and any `-L' flags needed to help the linker | |
143 | find those libraries. | |
2e368582 JB |
144 | |
145 | For example, here is a Makefile rule that builds a program named 'foo' | |
146 | from the object files ${FOO_OBJECTS}, and links them against Guile: | |
147 | ||
148 | foo: ${FOO_OBJECTS} | |
2adfe1c0 | 149 | ${CC} ${CFLAGS} ${FOO_OBJECTS} `guile-config link` -o foo |
2e368582 | 150 | |
e2d6569c JB |
151 | Previous Guile releases recommended that you use autoconf to detect |
152 | which of a predefined set of libraries were present on your system. | |
2adfe1c0 | 153 | It is more robust to use `guile-config', since it records exactly which |
e2d6569c JB |
154 | libraries the installed Guile library requires. |
155 | ||
2adfe1c0 JB |
156 | This was originally called `build-guile', but was renamed to |
157 | `guile-config' before Guile 1.3 was released, to be consistent with | |
158 | the analogous script for the GTK+ GUI toolkit, which is called | |
159 | `gtk-config'. | |
160 | ||
2e368582 | 161 | |
8aa5c148 JB |
162 | ** Use the GUILE_FLAGS macro in your configure.in file to find Guile. |
163 | ||
164 | If you are using the GNU autoconf package to configure your program, | |
165 | you can use the GUILE_FLAGS autoconf macro to call `guile-config' | |
166 | (described above) and gather the necessary values for use in your | |
167 | Makefiles. | |
168 | ||
169 | The GUILE_FLAGS macro expands to configure script code which runs the | |
170 | `guile-config' script, to find out where Guile's header files and | |
171 | libraries are installed. It sets two variables, marked for | |
172 | substitution, as by AC_SUBST. | |
173 | ||
174 | GUILE_CFLAGS --- flags to pass to a C or C++ compiler to build | |
175 | code that uses Guile header files. This is almost always just a | |
176 | -I flag. | |
177 | ||
178 | GUILE_LDFLAGS --- flags to pass to the linker to link a | |
179 | program against Guile. This includes `-lguile' for the Guile | |
180 | library itself, any libraries that Guile itself requires (like | |
181 | -lqthreads), and so on. It may also include a -L flag to tell the | |
182 | compiler where to find the libraries. | |
183 | ||
184 | GUILE_FLAGS is defined in the file guile.m4, in the top-level | |
185 | directory of the Guile distribution. You can copy it into your | |
186 | package's aclocal.m4 file, and then use it in your configure.in file. | |
187 | ||
188 | If you are using the `aclocal' program, distributed with GNU automake, | |
189 | to maintain your aclocal.m4 file, the Guile installation process | |
190 | installs guile.m4 where aclocal will find it. All you need to do is | |
191 | use GUILE_FLAGS in your configure.in file, and then run `aclocal'; | |
192 | this will copy the definition of GUILE_FLAGS into your aclocal.m4 | |
193 | file. | |
194 | ||
195 | ||
c484bf7f | 196 | * Changes to Scheme functions and syntax |
7ad3c1e7 | 197 | |
02755d59 | 198 | ** Multi-byte strings have been removed, as have multi-byte and wide |
e2d6569c JB |
199 | ports. We felt that these were the wrong approach to |
200 | internationalization support. | |
02755d59 | 201 | |
2e368582 JB |
202 | ** New function: readline [PROMPT] |
203 | Read a line from the terminal, and allow the user to edit it, | |
204 | prompting with PROMPT. READLINE provides a large set of Emacs-like | |
205 | editing commands, lets the user recall previously typed lines, and | |
206 | works on almost every kind of terminal, including dumb terminals. | |
207 | ||
208 | READLINE assumes that the cursor is at the beginning of the line when | |
209 | it is invoked. Thus, you can't print a prompt yourself, and then call | |
210 | READLINE; you need to package up your prompt as a string, pass it to | |
211 | the function, and let READLINE print the prompt itself. This is | |
212 | because READLINE needs to know the prompt's screen width. | |
213 | ||
8cd57bd0 JB |
214 | For Guile to provide this function, you must have the readline |
215 | library, version 2.1 or later, installed on your system. Readline is | |
216 | available via anonymous FTP from prep.ai.mit.edu in pub/gnu, or from | |
217 | any GNU mirror site. | |
2e368582 JB |
218 | |
219 | See also ADD-HISTORY function. | |
220 | ||
221 | ** New function: add-history STRING | |
222 | Add STRING as the most recent line in the history used by the READLINE | |
223 | command. READLINE does not add lines to the history itself; you must | |
224 | call ADD-HISTORY to make previous input available to the user. | |
225 | ||
8cd57bd0 JB |
226 | ** The behavior of the read-line function has changed. |
227 | ||
228 | This function now uses standard C library functions to read the line, | |
229 | for speed. This means that it doesn not respect the value of | |
230 | scm-line-incrementors; it assumes that lines are delimited with | |
231 | #\newline. | |
232 | ||
233 | (Note that this is read-line, the function that reads a line of text | |
234 | from a port, not readline, the function that reads a line from a | |
235 | terminal, providing full editing capabilities.) | |
236 | ||
1a0106ef JB |
237 | ** New module (ice-9 getopt-gnu-style): Parse command-line arguments. |
238 | ||
239 | This module provides some simple argument parsing. It exports one | |
240 | function: | |
241 | ||
242 | Function: getopt-gnu-style ARG-LS | |
243 | Parse a list of program arguments into an alist of option | |
244 | descriptions. | |
245 | ||
246 | Each item in the list of program arguments is examined to see if | |
247 | it meets the syntax of a GNU long-named option. An argument like | |
248 | `--MUMBLE' produces an element of the form (MUMBLE . #t) in the | |
249 | returned alist, where MUMBLE is a keyword object with the same | |
250 | name as the argument. An argument like `--MUMBLE=FROB' produces | |
251 | an element of the form (MUMBLE . FROB), where FROB is a string. | |
252 | ||
253 | As a special case, the returned alist also contains a pair whose | |
254 | car is the symbol `rest'. The cdr of this pair is a list | |
255 | containing all the items in the argument list that are not options | |
256 | of the form mentioned above. | |
257 | ||
258 | The argument `--' is treated specially: all items in the argument | |
259 | list appearing after such an argument are not examined, and are | |
260 | returned in the special `rest' list. | |
261 | ||
262 | This function does not parse normal single-character switches. | |
263 | You will need to parse them out of the `rest' list yourself. | |
264 | ||
8cd57bd0 JB |
265 | ** The read syntax for byte vectors and short vectors has changed. |
266 | ||
267 | Instead of #bytes(...), write #y(...). | |
268 | ||
269 | Instead of #short(...), write #h(...). | |
270 | ||
271 | This may seem nutty, but, like the other uniform vectors, byte vectors | |
272 | and short vectors want to have the same print and read syntax (and, | |
273 | more basic, want to have read syntax!). Changing the read syntax to | |
274 | use multiple characters after the hash sign breaks with the | |
275 | conventions used in R5RS and the conventions used for the other | |
276 | uniform vectors. It also introduces complexity in the current reader, | |
277 | both on the C and Scheme levels. (The Right solution is probably to | |
278 | change the syntax and prototypes for uniform vectors entirely.) | |
279 | ||
280 | ||
281 | ** The new module (ice-9 session) provides useful interactive functions. | |
282 | ||
283 | *** New procedure: (apropos REGEXP OPTION ...) | |
284 | ||
285 | Display a list of top-level variables whose names match REGEXP, and | |
286 | the modules they are imported from. Each OPTION should be one of the | |
287 | following symbols: | |
288 | ||
289 | value --- Show the value of each matching variable. | |
290 | shadow --- Show bindings shadowed by subsequently imported modules. | |
291 | full --- Same as both `shadow' and `value'. | |
292 | ||
293 | For example: | |
294 | ||
295 | guile> (apropos "trace" 'full) | |
296 | debug: trace #<procedure trace args> | |
297 | debug: untrace #<procedure untrace args> | |
298 | the-scm-module: display-backtrace #<compiled-closure #<primitive-procedure gsubr-apply>> | |
299 | the-scm-module: before-backtrace-hook () | |
300 | the-scm-module: backtrace #<primitive-procedure backtrace> | |
301 | the-scm-module: after-backtrace-hook () | |
302 | the-scm-module: has-shown-backtrace-hint? #f | |
303 | guile> | |
304 | ||
305 | ** There are new functions and syntax for working with macros. | |
306 | ||
307 | Guile implements macros as a special object type. Any variable whose | |
308 | top-level binding is a macro object acts as a macro. The macro object | |
309 | specifies how the expression should be transformed before evaluation. | |
310 | ||
311 | *** Macro objects now print in a reasonable way, resembling procedures. | |
312 | ||
313 | *** New function: (macro? OBJ) | |
314 | True iff OBJ is a macro object. | |
315 | ||
316 | *** New function: (primitive-macro? OBJ) | |
317 | Like (macro? OBJ), but true only if OBJ is one of the Guile primitive | |
318 | macro transformers, implemented in eval.c rather than Scheme code. | |
319 | ||
dbdd0c16 JB |
320 | Why do we have this function? |
321 | - For symmetry with procedure? and primitive-procedure?, | |
322 | - to allow custom print procedures to tell whether a macro is | |
323 | primitive, and display it differently, and | |
324 | - to allow compilers and user-written evaluators to distinguish | |
325 | builtin special forms from user-defined ones, which could be | |
326 | compiled. | |
327 | ||
8cd57bd0 JB |
328 | *** New function: (macro-type OBJ) |
329 | Return a value indicating what kind of macro OBJ is. Possible return | |
330 | values are: | |
331 | ||
332 | The symbol `syntax' --- a macro created by procedure->syntax. | |
333 | The symbol `macro' --- a macro created by procedure->macro. | |
334 | The symbol `macro!' --- a macro created by procedure->memoizing-macro. | |
335 | The boolean #f --- if OBJ is not a macro object. | |
336 | ||
337 | *** New function: (macro-name MACRO) | |
338 | Return the name of the macro object MACRO's procedure, as returned by | |
339 | procedure-name. | |
340 | ||
341 | *** New function: (macro-transformer MACRO) | |
342 | Return the transformer procedure for MACRO. | |
343 | ||
344 | *** New syntax: (use-syntax MODULE ... TRANSFORMER) | |
345 | ||
346 | Specify a new macro expander to use in the current module. Each | |
347 | MODULE is a module name, with the same meaning as in the `use-modules' | |
348 | form; each named module's exported bindings are added to the current | |
349 | top-level environment. TRANSFORMER is an expression evaluated in the | |
350 | resulting environment which must yield a procedure to use as the | |
351 | module's eval transformer: every expression evaluated in this module | |
352 | is passed to this function, and the result passed to the Guile | |
353 | interpreter. | |
354 | ||
355 | *** macro-eval! is removed. Use local-eval instead. | |
29521173 | 356 | |
8d9dcb3c MV |
357 | ** Some magic has been added to the printer to better handle user |
358 | written printing routines (like record printers, closure printers). | |
359 | ||
360 | The problem is that these user written routines must have access to | |
7fbd77df | 361 | the current `print-state' to be able to handle fancy things like |
8d9dcb3c MV |
362 | detection of circular references. These print-states have to be |
363 | passed to the builtin printing routines (display, write, etc) to | |
364 | properly continue the print chain. | |
365 | ||
366 | We didn't want to change all existing print code so that it | |
8cd57bd0 | 367 | explicitly passes thru a print state in addition to a port. Instead, |
8d9dcb3c MV |
368 | we extented the possible values that the builtin printing routines |
369 | accept as a `port'. In addition to a normal port, they now also take | |
370 | a pair of a normal port and a print-state. Printing will go to the | |
371 | port and the print-state will be used to control the detection of | |
372 | circular references, etc. If the builtin function does not care for a | |
373 | print-state, it is simply ignored. | |
374 | ||
375 | User written callbacks are now called with such a pair as their | |
376 | `port', but because every function now accepts this pair as a PORT | |
377 | argument, you don't have to worry about that. In fact, it is probably | |
378 | safest to not check for these pairs. | |
379 | ||
380 | However, it is sometimes necessary to continue a print chain on a | |
381 | different port, for example to get a intermediate string | |
382 | representation of the printed value, mangle that string somehow, and | |
383 | then to finally print the mangled string. Use the new function | |
384 | ||
385 | inherit-print-state OLD-PORT NEW-PORT | |
386 | ||
387 | for this. It constructs a new `port' that prints to NEW-PORT but | |
388 | inherits the print-state of OLD-PORT. | |
389 | ||
ef1ea498 MD |
390 | ** struct-vtable-offset renamed to vtable-offset-user |
391 | ||
392 | ** New constants: vtable-index-layout, vtable-index-vtable, vtable-index-printer | |
393 | ||
394 | ** There is now a fourth (optional) argument to make-vtable-vtable and | |
395 | make-struct when constructing new types (vtables). This argument | |
396 | initializes field vtable-index-printer of the vtable. | |
397 | ||
4851dc57 MV |
398 | ** The detection of circular references has been extended to structs. |
399 | That is, a structure that -- in the process of being printed -- prints | |
400 | itself does not lead to infinite recursion. | |
401 | ||
402 | ** There is now some basic support for fluids. Please read | |
403 | "libguile/fluid.h" to find out more. It is accessible from Scheme with | |
404 | the following functions and macros: | |
405 | ||
9c3fb66f MV |
406 | Function: make-fluid |
407 | ||
408 | Create a new fluid object. Fluids are not special variables or | |
409 | some other extension to the semantics of Scheme, but rather | |
410 | ordinary Scheme objects. You can store them into variables (that | |
411 | are still lexically scoped, of course) or into any other place you | |
412 | like. Every fluid has a initial value of `#f'. | |
04c76b58 | 413 | |
9c3fb66f | 414 | Function: fluid? OBJ |
04c76b58 | 415 | |
9c3fb66f | 416 | Test whether OBJ is a fluid. |
04c76b58 | 417 | |
9c3fb66f MV |
418 | Function: fluid-ref FLUID |
419 | Function: fluid-set! FLUID VAL | |
04c76b58 MV |
420 | |
421 | Access/modify the fluid FLUID. Modifications are only visible | |
422 | within the current dynamic root (that includes threads). | |
423 | ||
9c3fb66f MV |
424 | Function: with-fluids* FLUIDS VALUES THUNK |
425 | ||
426 | FLUIDS is a list of fluids and VALUES a corresponding list of | |
427 | values for these fluids. Before THUNK gets called the values are | |
428 | installed in the fluids and the old values of the fluids are | |
429 | saved in the VALUES list. When the flow of control leaves THUNK | |
430 | or reenters it, the values get swapped again. You might think of | |
431 | this as a `safe-fluid-excursion'. Note that the VALUES list is | |
432 | modified by `with-fluids*'. | |
433 | ||
434 | Macro: with-fluids ((FLUID VALUE) ...) FORM ... | |
435 | ||
436 | The same as `with-fluids*' but with a different syntax. It looks | |
437 | just like `let', but both FLUID and VALUE are evaluated. Remember, | |
438 | fluids are not special variables but ordinary objects. FLUID | |
439 | should evaluate to a fluid. | |
04c76b58 | 440 | |
e2d6569c | 441 | ** Changes to system call interfaces: |
64d01d13 | 442 | |
e2d6569c | 443 | *** close-port, close-input-port and close-output-port now return a |
64d01d13 GH |
444 | boolean instead of an `unspecified' object. #t means that the port |
445 | was successfully closed, while #f means it was already closed. It is | |
446 | also now possible for these procedures to raise an exception if an | |
447 | error occurs (some errors from write can be delayed until close.) | |
448 | ||
e2d6569c | 449 | *** the first argument to chmod, fcntl, ftell and fseek can now be a |
6afcd3b2 GH |
450 | file descriptor. |
451 | ||
e2d6569c | 452 | *** the third argument to fcntl is now optional. |
6afcd3b2 | 453 | |
e2d6569c | 454 | *** the first argument to chown can now be a file descriptor or a port. |
6afcd3b2 | 455 | |
e2d6569c | 456 | *** the argument to stat can now be a port. |
6afcd3b2 | 457 | |
e2d6569c | 458 | *** The following new procedures have been added (most use scsh |
64d01d13 GH |
459 | interfaces): |
460 | ||
e2d6569c | 461 | *** procedure: close PORT/FD |
ec4ab4fd GH |
462 | Similar to close-port (*note close-port: Closing Ports.), but also |
463 | works on file descriptors. A side effect of closing a file | |
464 | descriptor is that any ports using that file descriptor are moved | |
465 | to a different file descriptor and have their revealed counts set | |
466 | to zero. | |
467 | ||
e2d6569c | 468 | *** procedure: port->fdes PORT |
ec4ab4fd GH |
469 | Returns the integer file descriptor underlying PORT. As a side |
470 | effect the revealed count of PORT is incremented. | |
471 | ||
e2d6569c | 472 | *** procedure: fdes->ports FDES |
ec4ab4fd GH |
473 | Returns a list of existing ports which have FDES as an underlying |
474 | file descriptor, without changing their revealed counts. | |
475 | ||
e2d6569c | 476 | *** procedure: fdes->inport FDES |
ec4ab4fd GH |
477 | Returns an existing input port which has FDES as its underlying |
478 | file descriptor, if one exists, and increments its revealed count. | |
479 | Otherwise, returns a new input port with a revealed count of 1. | |
480 | ||
e2d6569c | 481 | *** procedure: fdes->outport FDES |
ec4ab4fd GH |
482 | Returns an existing output port which has FDES as its underlying |
483 | file descriptor, if one exists, and increments its revealed count. | |
484 | Otherwise, returns a new output port with a revealed count of 1. | |
485 | ||
486 | The next group of procedures perform a `dup2' system call, if NEWFD | |
487 | (an integer) is supplied, otherwise a `dup'. The file descriptor to be | |
488 | duplicated can be supplied as an integer or contained in a port. The | |
64d01d13 GH |
489 | type of value returned varies depending on which procedure is used. |
490 | ||
ec4ab4fd GH |
491 | All procedures also have the side effect when performing `dup2' that |
492 | any ports using NEWFD are moved to a different file descriptor and have | |
64d01d13 GH |
493 | their revealed counts set to zero. |
494 | ||
e2d6569c | 495 | *** procedure: dup->fdes PORT/FD [NEWFD] |
ec4ab4fd | 496 | Returns an integer file descriptor. |
64d01d13 | 497 | |
e2d6569c | 498 | *** procedure: dup->inport PORT/FD [NEWFD] |
ec4ab4fd | 499 | Returns a new input port using the new file descriptor. |
64d01d13 | 500 | |
e2d6569c | 501 | *** procedure: dup->outport PORT/FD [NEWFD] |
ec4ab4fd | 502 | Returns a new output port using the new file descriptor. |
64d01d13 | 503 | |
e2d6569c | 504 | *** procedure: dup PORT/FD [NEWFD] |
ec4ab4fd GH |
505 | Returns a new port if PORT/FD is a port, with the same mode as the |
506 | supplied port, otherwise returns an integer file descriptor. | |
64d01d13 | 507 | |
e2d6569c | 508 | *** procedure: dup->port PORT/FD MODE [NEWFD] |
ec4ab4fd GH |
509 | Returns a new port using the new file descriptor. MODE supplies a |
510 | mode string for the port (*note open-file: File Ports.). | |
64d01d13 | 511 | |
e2d6569c | 512 | *** procedure: setenv NAME VALUE |
ec4ab4fd GH |
513 | Modifies the environment of the current process, which is also the |
514 | default environment inherited by child processes. | |
64d01d13 | 515 | |
ec4ab4fd GH |
516 | If VALUE is `#f', then NAME is removed from the environment. |
517 | Otherwise, the string NAME=VALUE is added to the environment, | |
518 | replacing any existing string with name matching NAME. | |
64d01d13 | 519 | |
ec4ab4fd | 520 | The return value is unspecified. |
956055a9 | 521 | |
e2d6569c | 522 | *** procedure: truncate-file OBJ SIZE |
6afcd3b2 GH |
523 | Truncates the file referred to by OBJ to at most SIZE bytes. OBJ |
524 | can be a string containing a file name or an integer file | |
525 | descriptor or port open for output on the file. The underlying | |
526 | system calls are `truncate' and `ftruncate'. | |
527 | ||
528 | The return value is unspecified. | |
529 | ||
e2d6569c | 530 | *** procedure: setvbuf PORT MODE [SIZE] |
7a6f1ffa GH |
531 | Set the buffering mode for PORT. MODE can be: |
532 | `_IONBF' | |
533 | non-buffered | |
534 | ||
535 | `_IOLBF' | |
536 | line buffered | |
537 | ||
538 | `_IOFBF' | |
539 | block buffered, using a newly allocated buffer of SIZE bytes. | |
540 | However if SIZE is zero or unspecified, the port will be made | |
541 | non-buffered. | |
542 | ||
543 | This procedure should not be used after I/O has been performed with | |
544 | the port. | |
545 | ||
546 | Ports are usually block buffered by default, with a default buffer | |
547 | size. Procedures e.g., *Note open-file: File Ports, which accept a | |
548 | mode string allow `0' to be added to request an unbuffered port. | |
549 | ||
e2d6569c | 550 | *** procedure: fsync PORT/FD |
6afcd3b2 GH |
551 | Copies any unwritten data for the specified output file descriptor |
552 | to disk. If PORT/FD is a port, its buffer is flushed before the | |
553 | underlying file descriptor is fsync'd. The return value is | |
554 | unspecified. | |
555 | ||
e2d6569c | 556 | *** procedure: open-fdes PATH FLAGS [MODES] |
6afcd3b2 GH |
557 | Similar to `open' but returns a file descriptor instead of a port. |
558 | ||
e2d6569c | 559 | *** procedure: execle PATH ENV [ARG] ... |
6afcd3b2 GH |
560 | Similar to `execl', but the environment of the new process is |
561 | specified by ENV, which must be a list of strings as returned by | |
562 | the `environ' procedure. | |
563 | ||
564 | This procedure is currently implemented using the `execve' system | |
565 | call, but we call it `execle' because of its Scheme calling | |
566 | interface. | |
567 | ||
e2d6569c | 568 | *** procedure: strerror ERRNO |
ec4ab4fd GH |
569 | Returns the Unix error message corresponding to ERRNO, an integer. |
570 | ||
e2d6569c | 571 | *** procedure: primitive-exit [STATUS] |
6afcd3b2 GH |
572 | Terminate the current process without unwinding the Scheme stack. |
573 | This is would typically be useful after a fork. The exit status | |
574 | is STATUS if supplied, otherwise zero. | |
575 | ||
e2d6569c | 576 | *** procedure: times |
6afcd3b2 GH |
577 | Returns an object with information about real and processor time. |
578 | The following procedures accept such an object as an argument and | |
579 | return a selected component: | |
580 | ||
581 | `tms:clock' | |
582 | The current real time, expressed as time units relative to an | |
583 | arbitrary base. | |
584 | ||
585 | `tms:utime' | |
586 | The CPU time units used by the calling process. | |
587 | ||
588 | `tms:stime' | |
589 | The CPU time units used by the system on behalf of the | |
590 | calling process. | |
591 | ||
592 | `tms:cutime' | |
593 | The CPU time units used by terminated child processes of the | |
594 | calling process, whose status has been collected (e.g., using | |
595 | `waitpid'). | |
596 | ||
597 | `tms:cstime' | |
598 | Similarly, the CPU times units used by the system on behalf of | |
599 | terminated child processes. | |
7ad3c1e7 | 600 | |
e2d6569c JB |
601 | ** Removed: list-length |
602 | ** Removed: list-append, list-append! | |
603 | ** Removed: list-reverse, list-reverse! | |
604 | ||
605 | ** array-map renamed to array-map! | |
606 | ||
607 | ** serial-array-map renamed to serial-array-map! | |
608 | ||
660f41fa MD |
609 | ** catch doesn't take #f as first argument any longer |
610 | ||
611 | Previously, it was possible to pass #f instead of a key to `catch'. | |
612 | That would cause `catch' to pass a jump buffer object to the procedure | |
613 | passed as second argument. The procedure could then use this jump | |
614 | buffer objekt as an argument to throw. | |
615 | ||
616 | This mechanism has been removed since its utility doesn't motivate the | |
617 | extra complexity it introduces. | |
618 | ||
332d00f6 JB |
619 | ** The `#/' notation for lists now provokes a warning message from Guile. |
620 | This syntax will be removed from Guile in the near future. | |
621 | ||
622 | To disable the warning message, set the GUILE_HUSH environment | |
623 | variable to any non-empty value. | |
624 | ||
8cd57bd0 JB |
625 | ** The newline character now prints as `#\newline', following the |
626 | normal Scheme notation, not `#\nl'. | |
627 | ||
c484bf7f JB |
628 | * Changes to the gh_ interface |
629 | ||
8986901b JB |
630 | ** The gh_enter function now takes care of loading the Guile startup files. |
631 | gh_enter works by calling scm_boot_guile; see the remarks below. | |
632 | ||
5424b4f7 MD |
633 | ** Function: void gh_write (SCM x) |
634 | ||
635 | Write the printed representation of the scheme object x to the current | |
636 | output port. Corresponds to the scheme level `write'. | |
637 | ||
3a97e020 MD |
638 | ** gh_list_length renamed to gh_length. |
639 | ||
8d6787b6 MG |
640 | ** vector handling routines |
641 | ||
642 | Several major changes. In particular, gh_vector() now resembles | |
643 | (vector ...) (with a caveat -- see manual), and gh_make_vector() now | |
956328d2 MG |
644 | exists and behaves like (make-vector ...). gh_vset() and gh_vref() |
645 | have been renamed gh_vector_set_x() and gh_vector_ref(). Some missing | |
8d6787b6 MG |
646 | vector-related gh_ functions have been implemented. |
647 | ||
7fee59bd MG |
648 | ** pair and list routines |
649 | ||
650 | Implemented several of the R4RS pair and list functions that were | |
651 | missing. | |
652 | ||
171422a9 MD |
653 | ** gh_scm2doubles, gh_doubles2scm, gh_doubles2dvect |
654 | ||
655 | New function. Converts double arrays back and forth between Scheme | |
656 | and C. | |
657 | ||
c484bf7f JB |
658 | * Changes to the scm_ interface |
659 | ||
8986901b JB |
660 | ** The function scm_boot_guile now takes care of loading the startup files. |
661 | ||
662 | Guile's primary initialization function, scm_boot_guile, now takes | |
663 | care of loading `boot-9.scm', in the `ice-9' module, to initialize | |
664 | Guile, define the module system, and put together some standard | |
665 | bindings. It also loads `init.scm', which is intended to hold | |
666 | site-specific initialization code. | |
667 | ||
668 | Since Guile cannot operate properly until boot-9.scm is loaded, there | |
669 | is no reason to separate loading boot-9.scm from Guile's other | |
670 | initialization processes. | |
671 | ||
672 | This job used to be done by scm_compile_shell_switches, which didn't | |
673 | make much sense; in particular, it meant that people using Guile for | |
674 | non-shell-like applications had to jump through hoops to get Guile | |
675 | initialized properly. | |
676 | ||
677 | ** The function scm_compile_shell_switches no longer loads the startup files. | |
678 | Now, Guile always loads the startup files, whenever it is initialized; | |
679 | see the notes above for scm_boot_guile and scm_load_startup_files. | |
680 | ||
681 | ** Function: scm_load_startup_files | |
682 | This new function takes care of loading Guile's initialization file | |
683 | (`boot-9.scm'), and the site initialization file, `init.scm'. Since | |
684 | this is always called by the Guile initialization process, it's | |
685 | probably not too useful to call this yourself, but it's there anyway. | |
686 | ||
87148d9e JB |
687 | ** The semantics of smob marking have changed slightly. |
688 | ||
689 | The smob marking function (the `mark' member of the scm_smobfuns | |
690 | structure) is no longer responsible for setting the mark bit on the | |
691 | smob. The generic smob handling code in the garbage collector will | |
692 | set this bit. The mark function need only ensure that any other | |
693 | objects the smob refers to get marked. | |
694 | ||
695 | Note that this change means that the smob's GC8MARK bit is typically | |
696 | already set upon entry to the mark function. Thus, marking functions | |
697 | which look like this: | |
698 | ||
699 | { | |
700 | if (SCM_GC8MARKP (ptr)) | |
701 | return SCM_BOOL_F; | |
702 | SCM_SETGC8MARK (ptr); | |
703 | ... mark objects to which the smob refers ... | |
704 | } | |
705 | ||
706 | are now incorrect, since they will return early, and fail to mark any | |
707 | other objects the smob refers to. Some code in the Guile library used | |
708 | to work this way. | |
709 | ||
1cf84ea5 JB |
710 | ** The semantics of the I/O port functions in scm_ptobfuns have changed. |
711 | ||
712 | If you have implemented your own I/O port type, by writing the | |
713 | functions required by the scm_ptobfuns and then calling scm_newptob, | |
714 | you will need to change your functions slightly. | |
715 | ||
716 | The functions in a scm_ptobfuns structure now expect the port itself | |
717 | as their argument; they used to expect the `stream' member of the | |
718 | port's scm_port_table structure. This allows functions in an | |
719 | scm_ptobfuns structure to easily access the port's cell (and any flags | |
720 | it its CAR), and the port's scm_port_table structure. | |
721 | ||
722 | Guile now passes the I/O port itself as the `port' argument in the | |
723 | following scm_ptobfuns functions: | |
724 | ||
725 | int (*free) (SCM port); | |
726 | int (*fputc) (int, SCM port); | |
727 | int (*fputs) (char *, SCM port); | |
728 | scm_sizet (*fwrite) SCM_P ((char *ptr, | |
729 | scm_sizet size, | |
730 | scm_sizet nitems, | |
731 | SCM port)); | |
732 | int (*fflush) (SCM port); | |
733 | int (*fgetc) (SCM port); | |
734 | int (*fclose) (SCM port); | |
735 | ||
736 | The interfaces to the `mark', `print', `equalp', and `fgets' methods | |
737 | are unchanged. | |
738 | ||
739 | If you have existing code which defines its own port types, it is easy | |
740 | to convert your code to the new interface; simply apply SCM_STREAM to | |
741 | the port argument to yield the value you code used to expect. | |
742 | ||
743 | Note that since both the port and the stream have the same type in the | |
744 | C code --- they are both SCM values --- the C compiler will not remind | |
745 | you if you forget to update your scm_ptobfuns functions. | |
746 | ||
747 | ||
933a7411 MD |
748 | ** Function: int scm_internal_select (int fds, |
749 | SELECT_TYPE *rfds, | |
750 | SELECT_TYPE *wfds, | |
751 | SELECT_TYPE *efds, | |
752 | struct timeval *timeout); | |
753 | ||
754 | This is a replacement for the `select' function provided by the OS. | |
755 | It enables I/O blocking and sleeping to happen for one cooperative | |
756 | thread without blocking other threads. It also avoids busy-loops in | |
757 | these situations. It is intended that all I/O blocking and sleeping | |
758 | will finally go through this function. Currently, this function is | |
759 | only available on systems providing `gettimeofday' and `select'. | |
760 | ||
5424b4f7 MD |
761 | ** Function: SCM scm_internal_stack_catch (SCM tag, |
762 | scm_catch_body_t body, | |
763 | void *body_data, | |
764 | scm_catch_handler_t handler, | |
765 | void *handler_data) | |
766 | ||
767 | A new sibling to the other two C level `catch' functions | |
768 | scm_internal_catch and scm_internal_lazy_catch. Use it if you want | |
769 | the stack to be saved automatically into the variable `the-last-stack' | |
770 | (scm_the_last_stack_var) on error. This is necessary if you want to | |
771 | use advanced error reporting, such as calling scm_display_error and | |
772 | scm_display_backtrace. (They both take a stack object as argument.) | |
773 | ||
df366c26 MD |
774 | ** Function: SCM scm_spawn_thread (scm_catch_body_t body, |
775 | void *body_data, | |
776 | scm_catch_handler_t handler, | |
777 | void *handler_data) | |
778 | ||
779 | Spawns a new thread. It does a job similar to | |
780 | scm_call_with_new_thread but takes arguments more suitable when | |
781 | spawning threads from application C code. | |
782 | ||
88482b31 MD |
783 | ** The hook scm_error_callback has been removed. It was originally |
784 | intended as a way for the user to install his own error handler. But | |
785 | that method works badly since it intervenes between throw and catch, | |
786 | thereby changing the semantics of expressions like (catch #t ...). | |
787 | The correct way to do it is to use one of the C level catch functions | |
788 | in throw.c: scm_internal_catch/lazy_catch/stack_catch. | |
789 | ||
3a97e020 MD |
790 | ** Removed functions: |
791 | ||
792 | scm_obj_length, scm_list_length, scm_list_append, scm_list_append_x, | |
793 | scm_list_reverse, scm_list_reverse_x | |
794 | ||
795 | ** New macros: SCM_LISTn where n is one of the integers 0-9. | |
796 | ||
797 | These can be used for pretty list creation from C. The idea is taken | |
798 | from Erick Gallesio's STk. | |
799 | ||
298aa6e3 MD |
800 | ** scm_array_map renamed to scm_array_map_x |
801 | ||
527da704 MD |
802 | ** mbstrings are now removed |
803 | ||
804 | This means that the type codes scm_tc7_mb_string and | |
805 | scm_tc7_mb_substring has been removed. | |
806 | ||
8cd57bd0 JB |
807 | ** scm_gen_putc, scm_gen_puts, scm_gen_write, and scm_gen_getc have changed. |
808 | ||
809 | Since we no longer support multi-byte strings, these I/O functions | |
810 | have been simplified, and renamed. Here are their old names, and | |
811 | their new names and arguments: | |
812 | ||
813 | scm_gen_putc -> void scm_putc (int c, SCM port); | |
814 | scm_gen_puts -> void scm_puts (char *s, SCM port); | |
815 | scm_gen_write -> void scm_lfwrite (char *ptr, scm_sizet size, SCM port); | |
816 | scm_gen_getc -> void scm_getc (SCM port); | |
817 | ||
818 | ||
527da704 MD |
819 | ** The macros SCM_TYP7D and SCM_TYP7SD has been removed. |
820 | ||
821 | ** The macro SCM_TYP7S has taken the role of the old SCM_TYP7D | |
822 | ||
823 | SCM_TYP7S now masks away the bit which distinguishes substrings from | |
824 | strings. | |
825 | ||
660f41fa MD |
826 | ** scm_catch_body_t: Backward incompatible change! |
827 | ||
828 | Body functions to scm_internal_catch and friends do not any longer | |
829 | take a second argument. This is because it is no longer possible to | |
830 | pass a #f arg to catch. | |
831 | ||
a8e05009 JB |
832 | ** Calls to scm_protect_object and scm_unprotect now nest properly. |
833 | ||
834 | The function scm_protect_object protects its argument from being freed | |
835 | by the garbage collector. scm_unprotect_object removes that | |
836 | protection. | |
837 | ||
838 | These functions now nest properly. That is, for every object O, there | |
839 | is a counter which scm_protect_object(O) increments and | |
840 | scm_unprotect_object(O) decrements, if the counter is greater than | |
841 | zero. Every object's counter is zero when it is first created. If an | |
842 | object's counter is greater than zero, the garbage collector will not | |
843 | reclaim its storage. | |
844 | ||
845 | This allows you to use scm_protect_object in your code without | |
846 | worrying that some other function you call will call | |
847 | scm_unprotect_object, and allow it to be freed. Assuming that the | |
848 | functions you call are well-behaved, and unprotect only those objects | |
849 | they protect, you can follow the same rule and have confidence that | |
850 | objects will be freed only at appropriate times. | |
851 | ||
c484bf7f JB |
852 | \f |
853 | Changes in Guile 1.2 (released Tuesday, June 24 1997): | |
cf78e9e8 | 854 | |
737c9113 JB |
855 | * Changes to the distribution |
856 | ||
832b09ed JB |
857 | ** Nightly snapshots are now available from ftp.red-bean.com. |
858 | The old server, ftp.cyclic.com, has been relinquished to its rightful | |
859 | owner. | |
860 | ||
861 | Nightly snapshots of the Guile development sources are now available via | |
862 | anonymous FTP from ftp.red-bean.com, as /pub/guile/guile-snap.tar.gz. | |
863 | ||
864 | Via the web, that's: ftp://ftp.red-bean.com/pub/guile/guile-snap.tar.gz | |
865 | For getit, that's: ftp.red-bean.com:/pub/guile/guile-snap.tar.gz | |
866 | ||
0fcab5ed JB |
867 | ** To run Guile without installing it, the procedure has changed a bit. |
868 | ||
869 | If you used a separate build directory to compile Guile, you'll need | |
870 | to include the build directory in SCHEME_LOAD_PATH, as well as the | |
871 | source directory. See the `INSTALL' file for examples. | |
872 | ||
737c9113 JB |
873 | * Changes to the procedure for linking libguile with your programs |
874 | ||
94982a4e JB |
875 | ** The standard Guile load path for Scheme code now includes |
876 | $(datadir)/guile (usually /usr/local/share/guile). This means that | |
877 | you can install your own Scheme files there, and Guile will find them. | |
878 | (Previous versions of Guile only checked a directory whose name | |
879 | contained the Guile version number, so you had to re-install or move | |
880 | your Scheme sources each time you installed a fresh version of Guile.) | |
881 | ||
882 | The load path also includes $(datadir)/guile/site; we recommend | |
883 | putting individual Scheme files there. If you want to install a | |
884 | package with multiple source files, create a directory for them under | |
885 | $(datadir)/guile. | |
886 | ||
887 | ** Guile 1.2 will now use the Rx regular expression library, if it is | |
888 | installed on your system. When you are linking libguile into your own | |
889 | programs, this means you will have to link against -lguile, -lqt (if | |
890 | you configured Guile with thread support), and -lrx. | |
27590f82 JB |
891 | |
892 | If you are using autoconf to generate configuration scripts for your | |
893 | application, the following lines should suffice to add the appropriate | |
894 | libraries to your link command: | |
895 | ||
896 | ### Find Rx, quickthreads and libguile. | |
897 | AC_CHECK_LIB(rx, main) | |
898 | AC_CHECK_LIB(qt, main) | |
899 | AC_CHECK_LIB(guile, scm_shell) | |
900 | ||
94982a4e JB |
901 | The Guile 1.2 distribution does not contain sources for the Rx |
902 | library, as Guile 1.0 did. If you want to use Rx, you'll need to | |
903 | retrieve it from a GNU FTP site and install it separately. | |
904 | ||
b83b8bee JB |
905 | * Changes to Scheme functions and syntax |
906 | ||
e035e7e6 MV |
907 | ** The dynamic linking features of Guile are now enabled by default. |
908 | You can disable them by giving the `--disable-dynamic-linking' option | |
909 | to configure. | |
910 | ||
e035e7e6 MV |
911 | (dynamic-link FILENAME) |
912 | ||
913 | Find the object file denoted by FILENAME (a string) and link it | |
914 | into the running Guile application. When everything works out, | |
915 | return a Scheme object suitable for representing the linked object | |
916 | file. Otherwise an error is thrown. How object files are | |
917 | searched is system dependent. | |
918 | ||
919 | (dynamic-object? VAL) | |
920 | ||
921 | Determine whether VAL represents a dynamically linked object file. | |
922 | ||
923 | (dynamic-unlink DYNOBJ) | |
924 | ||
925 | Unlink the indicated object file from the application. DYNOBJ | |
926 | should be one of the values returned by `dynamic-link'. | |
927 | ||
928 | (dynamic-func FUNCTION DYNOBJ) | |
929 | ||
930 | Search the C function indicated by FUNCTION (a string or symbol) | |
931 | in DYNOBJ and return some Scheme object that can later be used | |
932 | with `dynamic-call' to actually call this function. Right now, | |
933 | these Scheme objects are formed by casting the address of the | |
934 | function to `long' and converting this number to its Scheme | |
935 | representation. | |
936 | ||
937 | (dynamic-call FUNCTION DYNOBJ) | |
938 | ||
939 | Call the C function indicated by FUNCTION and DYNOBJ. The | |
940 | function is passed no arguments and its return value is ignored. | |
941 | When FUNCTION is something returned by `dynamic-func', call that | |
942 | function and ignore DYNOBJ. When FUNCTION is a string (or symbol, | |
943 | etc.), look it up in DYNOBJ; this is equivalent to | |
944 | ||
945 | (dynamic-call (dynamic-func FUNCTION DYNOBJ) #f) | |
946 | ||
947 | Interrupts are deferred while the C function is executing (with | |
948 | SCM_DEFER_INTS/SCM_ALLOW_INTS). | |
949 | ||
950 | (dynamic-args-call FUNCTION DYNOBJ ARGS) | |
951 | ||
952 | Call the C function indicated by FUNCTION and DYNOBJ, but pass it | |
953 | some arguments and return its return value. The C function is | |
954 | expected to take two arguments and return an `int', just like | |
955 | `main': | |
956 | ||
957 | int c_func (int argc, char **argv); | |
958 | ||
959 | ARGS must be a list of strings and is converted into an array of | |
960 | `char *'. The array is passed in ARGV and its size in ARGC. The | |
961 | return value is converted to a Scheme number and returned from the | |
962 | call to `dynamic-args-call'. | |
963 | ||
0fcab5ed JB |
964 | When dynamic linking is disabled or not supported on your system, |
965 | the above functions throw errors, but they are still available. | |
966 | ||
e035e7e6 MV |
967 | Here is a small example that works on GNU/Linux: |
968 | ||
969 | (define libc-obj (dynamic-link "libc.so")) | |
970 | (dynamic-args-call 'rand libc-obj '()) | |
971 | ||
972 | See the file `libguile/DYNAMIC-LINKING' for additional comments. | |
973 | ||
27590f82 JB |
974 | ** The #/ syntax for module names is depreciated, and will be removed |
975 | in a future version of Guile. Instead of | |
976 | ||
977 | #/foo/bar/baz | |
978 | ||
979 | instead write | |
980 | ||
981 | (foo bar baz) | |
982 | ||
983 | The latter syntax is more consistent with existing Lisp practice. | |
984 | ||
5dade857 MV |
985 | ** Guile now does fancier printing of structures. Structures are the |
986 | underlying implementation for records, which in turn are used to | |
987 | implement modules, so all of these object now print differently and in | |
988 | a more informative way. | |
989 | ||
161029df JB |
990 | The Scheme printer will examine the builtin variable *struct-printer* |
991 | whenever it needs to print a structure object. When this variable is | |
992 | not `#f' it is deemed to be a procedure and will be applied to the | |
993 | structure object and the output port. When *struct-printer* is `#f' | |
994 | or the procedure return `#f' the structure object will be printed in | |
995 | the boring #<struct 80458270> form. | |
5dade857 MV |
996 | |
997 | This hook is used by some routines in ice-9/boot-9.scm to implement | |
998 | type specific printing routines. Please read the comments there about | |
999 | "printing structs". | |
1000 | ||
1001 | One of the more specific uses of structs are records. The printing | |
1002 | procedure that could be passed to MAKE-RECORD-TYPE is now actually | |
1003 | called. It should behave like a *struct-printer* procedure (described | |
1004 | above). | |
1005 | ||
b83b8bee JB |
1006 | ** Guile now supports a new R4RS-compliant syntax for keywords. A |
1007 | token of the form #:NAME, where NAME has the same syntax as a Scheme | |
1008 | symbol, is the external representation of the keyword named NAME. | |
1009 | Keyword objects print using this syntax as well, so values containing | |
1e5afba0 JB |
1010 | keyword objects can be read back into Guile. When used in an |
1011 | expression, keywords are self-quoting objects. | |
b83b8bee JB |
1012 | |
1013 | Guile suports this read syntax, and uses this print syntax, regardless | |
1014 | of the current setting of the `keyword' read option. The `keyword' | |
1015 | read option only controls whether Guile recognizes the `:NAME' syntax, | |
1016 | which is incompatible with R4RS. (R4RS says such token represent | |
1017 | symbols.) | |
737c9113 JB |
1018 | |
1019 | ** Guile has regular expression support again. Guile 1.0 included | |
1020 | functions for matching regular expressions, based on the Rx library. | |
1021 | In Guile 1.1, the Guile/Rx interface was removed to simplify the | |
1022 | distribution, and thus Guile had no regular expression support. Guile | |
94982a4e JB |
1023 | 1.2 again supports the most commonly used functions, and supports all |
1024 | of SCSH's regular expression functions. | |
2409cdfa | 1025 | |
94982a4e JB |
1026 | If your system does not include a POSIX regular expression library, |
1027 | and you have not linked Guile with a third-party regexp library such as | |
1028 | Rx, these functions will not be available. You can tell whether your | |
1029 | Guile installation includes regular expression support by checking | |
1030 | whether the `*features*' list includes the `regex' symbol. | |
737c9113 | 1031 | |
94982a4e | 1032 | *** regexp functions |
161029df | 1033 | |
94982a4e JB |
1034 | By default, Guile supports POSIX extended regular expressions. That |
1035 | means that the characters `(', `)', `+' and `?' are special, and must | |
1036 | be escaped if you wish to match the literal characters. | |
e1a191a8 | 1037 | |
94982a4e JB |
1038 | This regular expression interface was modeled after that implemented |
1039 | by SCSH, the Scheme Shell. It is intended to be upwardly compatible | |
1040 | with SCSH regular expressions. | |
1041 | ||
1042 | **** Function: string-match PATTERN STR [START] | |
1043 | Compile the string PATTERN into a regular expression and compare | |
1044 | it with STR. The optional numeric argument START specifies the | |
1045 | position of STR at which to begin matching. | |
1046 | ||
1047 | `string-match' returns a "match structure" which describes what, | |
1048 | if anything, was matched by the regular expression. *Note Match | |
1049 | Structures::. If STR does not match PATTERN at all, | |
1050 | `string-match' returns `#f'. | |
1051 | ||
1052 | Each time `string-match' is called, it must compile its PATTERN | |
1053 | argument into a regular expression structure. This operation is | |
1054 | expensive, which makes `string-match' inefficient if the same regular | |
1055 | expression is used several times (for example, in a loop). For better | |
1056 | performance, you can compile a regular expression in advance and then | |
1057 | match strings against the compiled regexp. | |
1058 | ||
1059 | **** Function: make-regexp STR [FLAGS] | |
1060 | Compile the regular expression described by STR, and return the | |
1061 | compiled regexp structure. If STR does not describe a legal | |
1062 | regular expression, `make-regexp' throws a | |
1063 | `regular-expression-syntax' error. | |
1064 | ||
1065 | FLAGS may be the bitwise-or of one or more of the following: | |
1066 | ||
1067 | **** Constant: regexp/extended | |
1068 | Use POSIX Extended Regular Expression syntax when interpreting | |
1069 | STR. If not set, POSIX Basic Regular Expression syntax is used. | |
1070 | If the FLAGS argument is omitted, we assume regexp/extended. | |
1071 | ||
1072 | **** Constant: regexp/icase | |
1073 | Do not differentiate case. Subsequent searches using the | |
1074 | returned regular expression will be case insensitive. | |
1075 | ||
1076 | **** Constant: regexp/newline | |
1077 | Match-any-character operators don't match a newline. | |
1078 | ||
1079 | A non-matching list ([^...]) not containing a newline matches a | |
1080 | newline. | |
1081 | ||
1082 | Match-beginning-of-line operator (^) matches the empty string | |
1083 | immediately after a newline, regardless of whether the FLAGS | |
1084 | passed to regexp-exec contain regexp/notbol. | |
1085 | ||
1086 | Match-end-of-line operator ($) matches the empty string | |
1087 | immediately before a newline, regardless of whether the FLAGS | |
1088 | passed to regexp-exec contain regexp/noteol. | |
1089 | ||
1090 | **** Function: regexp-exec REGEXP STR [START [FLAGS]] | |
1091 | Match the compiled regular expression REGEXP against `str'. If | |
1092 | the optional integer START argument is provided, begin matching | |
1093 | from that position in the string. Return a match structure | |
1094 | describing the results of the match, or `#f' if no match could be | |
1095 | found. | |
1096 | ||
1097 | FLAGS may be the bitwise-or of one or more of the following: | |
1098 | ||
1099 | **** Constant: regexp/notbol | |
1100 | The match-beginning-of-line operator always fails to match (but | |
1101 | see the compilation flag regexp/newline above) This flag may be | |
1102 | used when different portions of a string are passed to | |
1103 | regexp-exec and the beginning of the string should not be | |
1104 | interpreted as the beginning of the line. | |
1105 | ||
1106 | **** Constant: regexp/noteol | |
1107 | The match-end-of-line operator always fails to match (but see the | |
1108 | compilation flag regexp/newline above) | |
1109 | ||
1110 | **** Function: regexp? OBJ | |
1111 | Return `#t' if OBJ is a compiled regular expression, or `#f' | |
1112 | otherwise. | |
1113 | ||
1114 | Regular expressions are commonly used to find patterns in one string | |
1115 | and replace them with the contents of another string. | |
1116 | ||
1117 | **** Function: regexp-substitute PORT MATCH [ITEM...] | |
1118 | Write to the output port PORT selected contents of the match | |
1119 | structure MATCH. Each ITEM specifies what should be written, and | |
1120 | may be one of the following arguments: | |
1121 | ||
1122 | * A string. String arguments are written out verbatim. | |
1123 | ||
1124 | * An integer. The submatch with that number is written. | |
1125 | ||
1126 | * The symbol `pre'. The portion of the matched string preceding | |
1127 | the regexp match is written. | |
1128 | ||
1129 | * The symbol `post'. The portion of the matched string | |
1130 | following the regexp match is written. | |
1131 | ||
1132 | PORT may be `#f', in which case nothing is written; instead, | |
1133 | `regexp-substitute' constructs a string from the specified ITEMs | |
1134 | and returns that. | |
1135 | ||
1136 | **** Function: regexp-substitute/global PORT REGEXP TARGET [ITEM...] | |
1137 | Similar to `regexp-substitute', but can be used to perform global | |
1138 | substitutions on STR. Instead of taking a match structure as an | |
1139 | argument, `regexp-substitute/global' takes two string arguments: a | |
1140 | REGEXP string describing a regular expression, and a TARGET string | |
1141 | which should be matched against this regular expression. | |
1142 | ||
1143 | Each ITEM behaves as in REGEXP-SUBSTITUTE, with the following | |
1144 | exceptions: | |
1145 | ||
1146 | * A function may be supplied. When this function is called, it | |
1147 | will be passed one argument: a match structure for a given | |
1148 | regular expression match. It should return a string to be | |
1149 | written out to PORT. | |
1150 | ||
1151 | * The `post' symbol causes `regexp-substitute/global' to recurse | |
1152 | on the unmatched portion of STR. This *must* be supplied in | |
1153 | order to perform global search-and-replace on STR; if it is | |
1154 | not present among the ITEMs, then `regexp-substitute/global' | |
1155 | will return after processing a single match. | |
1156 | ||
1157 | *** Match Structures | |
1158 | ||
1159 | A "match structure" is the object returned by `string-match' and | |
1160 | `regexp-exec'. It describes which portion of a string, if any, matched | |
1161 | the given regular expression. Match structures include: a reference to | |
1162 | the string that was checked for matches; the starting and ending | |
1163 | positions of the regexp match; and, if the regexp included any | |
1164 | parenthesized subexpressions, the starting and ending positions of each | |
1165 | submatch. | |
1166 | ||
1167 | In each of the regexp match functions described below, the `match' | |
1168 | argument must be a match structure returned by a previous call to | |
1169 | `string-match' or `regexp-exec'. Most of these functions return some | |
1170 | information about the original target string that was matched against a | |
1171 | regular expression; we will call that string TARGET for easy reference. | |
1172 | ||
1173 | **** Function: regexp-match? OBJ | |
1174 | Return `#t' if OBJ is a match structure returned by a previous | |
1175 | call to `regexp-exec', or `#f' otherwise. | |
1176 | ||
1177 | **** Function: match:substring MATCH [N] | |
1178 | Return the portion of TARGET matched by subexpression number N. | |
1179 | Submatch 0 (the default) represents the entire regexp match. If | |
1180 | the regular expression as a whole matched, but the subexpression | |
1181 | number N did not match, return `#f'. | |
1182 | ||
1183 | **** Function: match:start MATCH [N] | |
1184 | Return the starting position of submatch number N. | |
1185 | ||
1186 | **** Function: match:end MATCH [N] | |
1187 | Return the ending position of submatch number N. | |
1188 | ||
1189 | **** Function: match:prefix MATCH | |
1190 | Return the unmatched portion of TARGET preceding the regexp match. | |
1191 | ||
1192 | **** Function: match:suffix MATCH | |
1193 | Return the unmatched portion of TARGET following the regexp match. | |
1194 | ||
1195 | **** Function: match:count MATCH | |
1196 | Return the number of parenthesized subexpressions from MATCH. | |
1197 | Note that the entire regular expression match itself counts as a | |
1198 | subexpression, and failed submatches are included in the count. | |
1199 | ||
1200 | **** Function: match:string MATCH | |
1201 | Return the original TARGET string. | |
1202 | ||
1203 | *** Backslash Escapes | |
1204 | ||
1205 | Sometimes you will want a regexp to match characters like `*' or `$' | |
1206 | exactly. For example, to check whether a particular string represents | |
1207 | a menu entry from an Info node, it would be useful to match it against | |
1208 | a regexp like `^* [^:]*::'. However, this won't work; because the | |
1209 | asterisk is a metacharacter, it won't match the `*' at the beginning of | |
1210 | the string. In this case, we want to make the first asterisk un-magic. | |
1211 | ||
1212 | You can do this by preceding the metacharacter with a backslash | |
1213 | character `\'. (This is also called "quoting" the metacharacter, and | |
1214 | is known as a "backslash escape".) When Guile sees a backslash in a | |
1215 | regular expression, it considers the following glyph to be an ordinary | |
1216 | character, no matter what special meaning it would ordinarily have. | |
1217 | Therefore, we can make the above example work by changing the regexp to | |
1218 | `^\* [^:]*::'. The `\*' sequence tells the regular expression engine | |
1219 | to match only a single asterisk in the target string. | |
1220 | ||
1221 | Since the backslash is itself a metacharacter, you may force a | |
1222 | regexp to match a backslash in the target string by preceding the | |
1223 | backslash with itself. For example, to find variable references in a | |
1224 | TeX program, you might want to find occurrences of the string `\let\' | |
1225 | followed by any number of alphabetic characters. The regular expression | |
1226 | `\\let\\[A-Za-z]*' would do this: the double backslashes in the regexp | |
1227 | each match a single backslash in the target string. | |
1228 | ||
1229 | **** Function: regexp-quote STR | |
1230 | Quote each special character found in STR with a backslash, and | |
1231 | return the resulting string. | |
1232 | ||
1233 | *Very important:* Using backslash escapes in Guile source code (as | |
1234 | in Emacs Lisp or C) can be tricky, because the backslash character has | |
1235 | special meaning for the Guile reader. For example, if Guile encounters | |
1236 | the character sequence `\n' in the middle of a string while processing | |
1237 | Scheme code, it replaces those characters with a newline character. | |
1238 | Similarly, the character sequence `\t' is replaced by a horizontal tab. | |
1239 | Several of these "escape sequences" are processed by the Guile reader | |
1240 | before your code is executed. Unrecognized escape sequences are | |
1241 | ignored: if the characters `\*' appear in a string, they will be | |
1242 | translated to the single character `*'. | |
1243 | ||
1244 | This translation is obviously undesirable for regular expressions, | |
1245 | since we want to be able to include backslashes in a string in order to | |
1246 | escape regexp metacharacters. Therefore, to make sure that a backslash | |
1247 | is preserved in a string in your Guile program, you must use *two* | |
1248 | consecutive backslashes: | |
1249 | ||
1250 | (define Info-menu-entry-pattern (make-regexp "^\\* [^:]*")) | |
1251 | ||
1252 | The string in this example is preprocessed by the Guile reader before | |
1253 | any code is executed. The resulting argument to `make-regexp' is the | |
1254 | string `^\* [^:]*', which is what we really want. | |
1255 | ||
1256 | This also means that in order to write a regular expression that | |
1257 | matches a single backslash character, the regular expression string in | |
1258 | the source code must include *four* backslashes. Each consecutive pair | |
1259 | of backslashes gets translated by the Guile reader to a single | |
1260 | backslash, and the resulting double-backslash is interpreted by the | |
1261 | regexp engine as matching a single backslash character. Hence: | |
1262 | ||
1263 | (define tex-variable-pattern (make-regexp "\\\\let\\\\=[A-Za-z]*")) | |
1264 | ||
1265 | The reason for the unwieldiness of this syntax is historical. Both | |
1266 | regular expression pattern matchers and Unix string processing systems | |
1267 | have traditionally used backslashes with the special meanings described | |
1268 | above. The POSIX regular expression specification and ANSI C standard | |
1269 | both require these semantics. Attempting to abandon either convention | |
1270 | would cause other kinds of compatibility problems, possibly more severe | |
1271 | ones. Therefore, without extending the Scheme reader to support | |
1272 | strings with different quoting conventions (an ungainly and confusing | |
1273 | extension when implemented in other languages), we must adhere to this | |
1274 | cumbersome escape syntax. | |
1275 | ||
7ad3c1e7 GH |
1276 | * Changes to the gh_ interface |
1277 | ||
1278 | * Changes to the scm_ interface | |
1279 | ||
1280 | * Changes to system call interfaces: | |
94982a4e | 1281 | |
7ad3c1e7 | 1282 | ** The value returned by `raise' is now unspecified. It throws an exception |
e1a191a8 GH |
1283 | if an error occurs. |
1284 | ||
94982a4e | 1285 | *** A new procedure `sigaction' can be used to install signal handlers |
115b09a5 GH |
1286 | |
1287 | (sigaction signum [action] [flags]) | |
1288 | ||
1289 | signum is the signal number, which can be specified using the value | |
1290 | of SIGINT etc. | |
1291 | ||
1292 | If action is omitted, sigaction returns a pair: the CAR is the current | |
1293 | signal hander, which will be either an integer with the value SIG_DFL | |
1294 | (default action) or SIG_IGN (ignore), or the Scheme procedure which | |
1295 | handles the signal, or #f if a non-Scheme procedure handles the | |
1296 | signal. The CDR contains the current sigaction flags for the handler. | |
1297 | ||
1298 | If action is provided, it is installed as the new handler for signum. | |
1299 | action can be a Scheme procedure taking one argument, or the value of | |
1300 | SIG_DFL (default action) or SIG_IGN (ignore), or #f to restore | |
1301 | whatever signal handler was installed before sigaction was first used. | |
1302 | Flags can optionally be specified for the new handler (SA_RESTART is | |
1303 | always used if the system provides it, so need not be specified.) The | |
1304 | return value is a pair with information about the old handler as | |
1305 | described above. | |
1306 | ||
1307 | This interface does not provide access to the "signal blocking" | |
1308 | facility. Maybe this is not needed, since the thread support may | |
1309 | provide solutions to the problem of consistent access to data | |
1310 | structures. | |
e1a191a8 | 1311 | |
94982a4e | 1312 | *** A new procedure `flush-all-ports' is equivalent to running |
89ea5b7c GH |
1313 | `force-output' on every port open for output. |
1314 | ||
94982a4e JB |
1315 | ** Guile now provides information on how it was built, via the new |
1316 | global variable, %guile-build-info. This variable records the values | |
1317 | of the standard GNU makefile directory variables as an assocation | |
1318 | list, mapping variable names (symbols) onto directory paths (strings). | |
1319 | For example, to find out where the Guile link libraries were | |
1320 | installed, you can say: | |
1321 | ||
1322 | guile -c "(display (assq-ref %guile-build-info 'libdir)) (newline)" | |
1323 | ||
1324 | ||
1325 | * Changes to the scm_ interface | |
1326 | ||
1327 | ** The new function scm_handle_by_message_noexit is just like the | |
1328 | existing scm_handle_by_message function, except that it doesn't call | |
1329 | exit to terminate the process. Instead, it prints a message and just | |
1330 | returns #f. This might be a more appropriate catch-all handler for | |
1331 | new dynamic roots and threads. | |
1332 | ||
cf78e9e8 | 1333 | \f |
c484bf7f | 1334 | Changes in Guile 1.1 (released Friday, May 16 1997): |
f3b1485f JB |
1335 | |
1336 | * Changes to the distribution. | |
1337 | ||
1338 | The Guile 1.0 distribution has been split up into several smaller | |
1339 | pieces: | |
1340 | guile-core --- the Guile interpreter itself. | |
1341 | guile-tcltk --- the interface between the Guile interpreter and | |
1342 | Tcl/Tk; Tcl is an interpreter for a stringy language, and Tk | |
1343 | is a toolkit for building graphical user interfaces. | |
1344 | guile-rgx-ctax --- the interface between Guile and the Rx regular | |
1345 | expression matcher, and the translator for the Ctax | |
1346 | programming language. These are packaged together because the | |
1347 | Ctax translator uses Rx to parse Ctax source code. | |
1348 | ||
095936d2 JB |
1349 | This NEWS file describes the changes made to guile-core since the 1.0 |
1350 | release. | |
1351 | ||
48d224d7 JB |
1352 | We no longer distribute the documentation, since it was either out of |
1353 | date, or incomplete. As soon as we have current documentation, we | |
1354 | will distribute it. | |
1355 | ||
0fcab5ed JB |
1356 | |
1357 | ||
f3b1485f JB |
1358 | * Changes to the stand-alone interpreter |
1359 | ||
48d224d7 JB |
1360 | ** guile now accepts command-line arguments compatible with SCSH, Olin |
1361 | Shivers' Scheme Shell. | |
1362 | ||
1363 | In general, arguments are evaluated from left to right, but there are | |
1364 | exceptions. The following switches stop argument processing, and | |
1365 | stash all remaining command-line arguments as the value returned by | |
1366 | the (command-line) function. | |
1367 | -s SCRIPT load Scheme source code from FILE, and exit | |
1368 | -c EXPR evalute Scheme expression EXPR, and exit | |
1369 | -- stop scanning arguments; run interactively | |
1370 | ||
1371 | The switches below are processed as they are encountered. | |
1372 | -l FILE load Scheme source code from FILE | |
1373 | -e FUNCTION after reading script, apply FUNCTION to | |
1374 | command line arguments | |
1375 | -ds do -s script at this point | |
1376 | --emacs enable Emacs protocol (experimental) | |
1377 | -h, --help display this help and exit | |
1378 | -v, --version display version information and exit | |
1379 | \ read arguments from following script lines | |
1380 | ||
1381 | So, for example, here is a Guile script named `ekko' (thanks, Olin) | |
1382 | which re-implements the traditional "echo" command: | |
1383 | ||
1384 | #!/usr/local/bin/guile -s | |
1385 | !# | |
1386 | (define (main args) | |
1387 | (map (lambda (arg) (display arg) (display " ")) | |
1388 | (cdr args)) | |
1389 | (newline)) | |
1390 | ||
1391 | (main (command-line)) | |
1392 | ||
1393 | Suppose we invoke this script as follows: | |
1394 | ||
1395 | ekko a speckled gecko | |
1396 | ||
1397 | Through the magic of Unix script processing (triggered by the `#!' | |
1398 | token at the top of the file), /usr/local/bin/guile receives the | |
1399 | following list of command-line arguments: | |
1400 | ||
1401 | ("-s" "./ekko" "a" "speckled" "gecko") | |
1402 | ||
1403 | Unix inserts the name of the script after the argument specified on | |
1404 | the first line of the file (in this case, "-s"), and then follows that | |
1405 | with the arguments given to the script. Guile loads the script, which | |
1406 | defines the `main' function, and then applies it to the list of | |
1407 | remaining command-line arguments, ("a" "speckled" "gecko"). | |
1408 | ||
095936d2 JB |
1409 | In Unix, the first line of a script file must take the following form: |
1410 | ||
1411 | #!INTERPRETER ARGUMENT | |
1412 | ||
1413 | where INTERPRETER is the absolute filename of the interpreter | |
1414 | executable, and ARGUMENT is a single command-line argument to pass to | |
1415 | the interpreter. | |
1416 | ||
1417 | You may only pass one argument to the interpreter, and its length is | |
1418 | limited. These restrictions can be annoying to work around, so Guile | |
1419 | provides a general mechanism (borrowed from, and compatible with, | |
1420 | SCSH) for circumventing them. | |
1421 | ||
1422 | If the ARGUMENT in a Guile script is a single backslash character, | |
1423 | `\', Guile will open the script file, parse arguments from its second | |
1424 | and subsequent lines, and replace the `\' with them. So, for example, | |
1425 | here is another implementation of the `ekko' script: | |
1426 | ||
1427 | #!/usr/local/bin/guile \ | |
1428 | -e main -s | |
1429 | !# | |
1430 | (define (main args) | |
1431 | (for-each (lambda (arg) (display arg) (display " ")) | |
1432 | (cdr args)) | |
1433 | (newline)) | |
1434 | ||
1435 | If the user invokes this script as follows: | |
1436 | ||
1437 | ekko a speckled gecko | |
1438 | ||
1439 | Unix expands this into | |
1440 | ||
1441 | /usr/local/bin/guile \ ekko a speckled gecko | |
1442 | ||
1443 | When Guile sees the `\' argument, it replaces it with the arguments | |
1444 | read from the second line of the script, producing: | |
1445 | ||
1446 | /usr/local/bin/guile -e main -s ekko a speckled gecko | |
1447 | ||
1448 | This tells Guile to load the `ekko' script, and apply the function | |
1449 | `main' to the argument list ("a" "speckled" "gecko"). | |
1450 | ||
1451 | Here is how Guile parses the command-line arguments: | |
1452 | - Each space character terminates an argument. This means that two | |
1453 | spaces in a row introduce an empty-string argument. | |
1454 | - The tab character is not permitted (unless you quote it with the | |
1455 | backslash character, as described below), to avoid confusion. | |
1456 | - The newline character terminates the sequence of arguments, and will | |
1457 | also terminate a final non-empty argument. (However, a newline | |
1458 | following a space will not introduce a final empty-string argument; | |
1459 | it only terminates the argument list.) | |
1460 | - The backslash character is the escape character. It escapes | |
1461 | backslash, space, tab, and newline. The ANSI C escape sequences | |
1462 | like \n and \t are also supported. These produce argument | |
1463 | constituents; the two-character combination \n doesn't act like a | |
1464 | terminating newline. The escape sequence \NNN for exactly three | |
1465 | octal digits reads as the character whose ASCII code is NNN. As | |
1466 | above, characters produced this way are argument constituents. | |
1467 | Backslash followed by other characters is not allowed. | |
1468 | ||
48d224d7 JB |
1469 | * Changes to the procedure for linking libguile with your programs |
1470 | ||
1471 | ** Guile now builds and installs a shared guile library, if your | |
1472 | system support shared libraries. (It still builds a static library on | |
1473 | all systems.) Guile automatically detects whether your system | |
1474 | supports shared libraries. To prevent Guile from buildisg shared | |
1475 | libraries, pass the `--disable-shared' flag to the configure script. | |
1476 | ||
1477 | Guile takes longer to compile when it builds shared libraries, because | |
1478 | it must compile every file twice --- once to produce position- | |
1479 | independent object code, and once to produce normal object code. | |
1480 | ||
1481 | ** The libthreads library has been merged into libguile. | |
1482 | ||
1483 | To link a program against Guile, you now need only link against | |
1484 | -lguile and -lqt; -lthreads is no longer needed. If you are using | |
1485 | autoconf to generate configuration scripts for your application, the | |
1486 | following lines should suffice to add the appropriate libraries to | |
1487 | your link command: | |
1488 | ||
1489 | ### Find quickthreads and libguile. | |
1490 | AC_CHECK_LIB(qt, main) | |
1491 | AC_CHECK_LIB(guile, scm_shell) | |
f3b1485f JB |
1492 | |
1493 | * Changes to Scheme functions | |
1494 | ||
095936d2 JB |
1495 | ** Guile Scheme's special syntax for keyword objects is now optional, |
1496 | and disabled by default. | |
1497 | ||
1498 | The syntax variation from R4RS made it difficult to port some | |
1499 | interesting packages to Guile. The routines which accepted keyword | |
1500 | arguments (mostly in the module system) have been modified to also | |
1501 | accept symbols whose names begin with `:'. | |
1502 | ||
1503 | To change the keyword syntax, you must first import the (ice-9 debug) | |
1504 | module: | |
1505 | (use-modules (ice-9 debug)) | |
1506 | ||
1507 | Then you can enable the keyword syntax as follows: | |
1508 | (read-set! keywords 'prefix) | |
1509 | ||
1510 | To disable keyword syntax, do this: | |
1511 | (read-set! keywords #f) | |
1512 | ||
1513 | ** Many more primitive functions accept shared substrings as | |
1514 | arguments. In the past, these functions required normal, mutable | |
1515 | strings as arguments, although they never made use of this | |
1516 | restriction. | |
1517 | ||
1518 | ** The uniform array functions now operate on byte vectors. These | |
1519 | functions are `array-fill!', `serial-array-copy!', `array-copy!', | |
1520 | `serial-array-map', `array-map', `array-for-each', and | |
1521 | `array-index-map!'. | |
1522 | ||
1523 | ** The new functions `trace' and `untrace' implement simple debugging | |
1524 | support for Scheme functions. | |
1525 | ||
1526 | The `trace' function accepts any number of procedures as arguments, | |
1527 | and tells the Guile interpreter to display each procedure's name and | |
1528 | arguments each time the procedure is invoked. When invoked with no | |
1529 | arguments, `trace' returns the list of procedures currently being | |
1530 | traced. | |
1531 | ||
1532 | The `untrace' function accepts any number of procedures as arguments, | |
1533 | and tells the Guile interpreter not to trace them any more. When | |
1534 | invoked with no arguments, `untrace' untraces all curretly traced | |
1535 | procedures. | |
1536 | ||
1537 | The tracing in Guile has an advantage over most other systems: we | |
1538 | don't create new procedure objects, but mark the procedure objects | |
1539 | themselves. This means that anonymous and internal procedures can be | |
1540 | traced. | |
1541 | ||
1542 | ** The function `assert-repl-prompt' has been renamed to | |
1543 | `set-repl-prompt!'. It takes one argument, PROMPT. | |
1544 | - If PROMPT is #f, the Guile read-eval-print loop will not prompt. | |
1545 | - If PROMPT is a string, we use it as a prompt. | |
1546 | - If PROMPT is a procedure accepting no arguments, we call it, and | |
1547 | display the result as a prompt. | |
1548 | - Otherwise, we display "> ". | |
1549 | ||
1550 | ** The new function `eval-string' reads Scheme expressions from a | |
1551 | string and evaluates them, returning the value of the last expression | |
1552 | in the string. If the string contains no expressions, it returns an | |
1553 | unspecified value. | |
1554 | ||
1555 | ** The new function `thunk?' returns true iff its argument is a | |
1556 | procedure of zero arguments. | |
1557 | ||
1558 | ** `defined?' is now a builtin function, instead of syntax. This | |
1559 | means that its argument should be quoted. It returns #t iff its | |
1560 | argument is bound in the current module. | |
1561 | ||
1562 | ** The new syntax `use-modules' allows you to add new modules to your | |
1563 | environment without re-typing a complete `define-module' form. It | |
1564 | accepts any number of module names as arguments, and imports their | |
1565 | public bindings into the current module. | |
1566 | ||
1567 | ** The new function (module-defined? NAME MODULE) returns true iff | |
1568 | NAME, a symbol, is defined in MODULE, a module object. | |
1569 | ||
1570 | ** The new function `builtin-bindings' creates and returns a hash | |
1571 | table containing copies of all the root module's bindings. | |
1572 | ||
1573 | ** The new function `builtin-weak-bindings' does the same as | |
1574 | `builtin-bindings', but creates a doubly-weak hash table. | |
1575 | ||
1576 | ** The `equal?' function now considers variable objects to be | |
1577 | equivalent if they have the same name and the same value. | |
1578 | ||
1579 | ** The new function `command-line' returns the command-line arguments | |
1580 | given to Guile, as a list of strings. | |
1581 | ||
1582 | When using guile as a script interpreter, `command-line' returns the | |
1583 | script's arguments; those processed by the interpreter (like `-s' or | |
1584 | `-c') are omitted. (In other words, you get the normal, expected | |
1585 | behavior.) Any application that uses scm_shell to process its | |
1586 | command-line arguments gets this behavior as well. | |
1587 | ||
1588 | ** The new function `load-user-init' looks for a file called `.guile' | |
1589 | in the user's home directory, and loads it if it exists. This is | |
1590 | mostly for use by the code generated by scm_compile_shell_switches, | |
1591 | but we thought it might also be useful in other circumstances. | |
1592 | ||
1593 | ** The new function `log10' returns the base-10 logarithm of its | |
1594 | argument. | |
1595 | ||
1596 | ** Changes to I/O functions | |
1597 | ||
1598 | *** The functions `read', `primitive-load', `read-and-eval!', and | |
1599 | `primitive-load-path' no longer take optional arguments controlling | |
1600 | case insensitivity and a `#' parser. | |
1601 | ||
1602 | Case sensitivity is now controlled by a read option called | |
1603 | `case-insensitive'. The user can add new `#' syntaxes with the | |
1604 | `read-hash-extend' function (see below). | |
1605 | ||
1606 | *** The new function `read-hash-extend' allows the user to change the | |
1607 | syntax of Guile Scheme in a somewhat controlled way. | |
1608 | ||
1609 | (read-hash-extend CHAR PROC) | |
1610 | When parsing S-expressions, if we read a `#' character followed by | |
1611 | the character CHAR, use PROC to parse an object from the stream. | |
1612 | If PROC is #f, remove any parsing procedure registered for CHAR. | |
1613 | ||
1614 | The reader applies PROC to two arguments: CHAR and an input port. | |
1615 | ||
1616 | *** The new functions read-delimited and read-delimited! provide a | |
1617 | general mechanism for doing delimited input on streams. | |
1618 | ||
1619 | (read-delimited DELIMS [PORT HANDLE-DELIM]) | |
1620 | Read until we encounter one of the characters in DELIMS (a string), | |
1621 | or end-of-file. PORT is the input port to read from; it defaults to | |
1622 | the current input port. The HANDLE-DELIM parameter determines how | |
1623 | the terminating character is handled; it should be one of the | |
1624 | following symbols: | |
1625 | ||
1626 | 'trim omit delimiter from result | |
1627 | 'peek leave delimiter character in input stream | |
1628 | 'concat append delimiter character to returned value | |
1629 | 'split return a pair: (RESULT . TERMINATOR) | |
1630 | ||
1631 | HANDLE-DELIM defaults to 'peek. | |
1632 | ||
1633 | (read-delimited! DELIMS BUF [PORT HANDLE-DELIM START END]) | |
1634 | A side-effecting variant of `read-delimited'. | |
1635 | ||
1636 | The data is written into the string BUF at the indices in the | |
1637 | half-open interval [START, END); the default interval is the whole | |
1638 | string: START = 0 and END = (string-length BUF). The values of | |
1639 | START and END must specify a well-defined interval in BUF, i.e. | |
1640 | 0 <= START <= END <= (string-length BUF). | |
1641 | ||
1642 | It returns NBYTES, the number of bytes read. If the buffer filled | |
1643 | up without a delimiter character being found, it returns #f. If the | |
1644 | port is at EOF when the read starts, it returns the EOF object. | |
1645 | ||
1646 | If an integer is returned (i.e., the read is successfully terminated | |
1647 | by reading a delimiter character), then the HANDLE-DELIM parameter | |
1648 | determines how to handle the terminating character. It is described | |
1649 | above, and defaults to 'peek. | |
1650 | ||
1651 | (The descriptions of these functions were borrowed from the SCSH | |
1652 | manual, by Olin Shivers and Brian Carlstrom.) | |
1653 | ||
1654 | *** The `%read-delimited!' function is the primitive used to implement | |
1655 | `read-delimited' and `read-delimited!'. | |
1656 | ||
1657 | (%read-delimited! DELIMS BUF GOBBLE? [PORT START END]) | |
1658 | ||
1659 | This returns a pair of values: (TERMINATOR . NUM-READ). | |
1660 | - TERMINATOR describes why the read was terminated. If it is a | |
1661 | character or the eof object, then that is the value that terminated | |
1662 | the read. If it is #f, the function filled the buffer without finding | |
1663 | a delimiting character. | |
1664 | - NUM-READ is the number of characters read into BUF. | |
1665 | ||
1666 | If the read is successfully terminated by reading a delimiter | |
1667 | character, then the gobble? parameter determines what to do with the | |
1668 | terminating character. If true, the character is removed from the | |
1669 | input stream; if false, the character is left in the input stream | |
1670 | where a subsequent read operation will retrieve it. In either case, | |
1671 | the character is also the first value returned by the procedure call. | |
1672 | ||
1673 | (The descriptions of this function was borrowed from the SCSH manual, | |
1674 | by Olin Shivers and Brian Carlstrom.) | |
1675 | ||
1676 | *** The `read-line' and `read-line!' functions have changed; they now | |
1677 | trim the terminator by default; previously they appended it to the | |
1678 | returned string. For the old behavior, use (read-line PORT 'concat). | |
1679 | ||
1680 | *** The functions `uniform-array-read!' and `uniform-array-write!' now | |
1681 | take new optional START and END arguments, specifying the region of | |
1682 | the array to read and write. | |
1683 | ||
f348c807 JB |
1684 | *** The `ungetc-char-ready?' function has been removed. We feel it's |
1685 | inappropriate for an interface to expose implementation details this | |
1686 | way. | |
095936d2 JB |
1687 | |
1688 | ** Changes to the Unix library and system call interface | |
1689 | ||
1690 | *** The new fcntl function provides access to the Unix `fcntl' system | |
1691 | call. | |
1692 | ||
1693 | (fcntl PORT COMMAND VALUE) | |
1694 | Apply COMMAND to PORT's file descriptor, with VALUE as an argument. | |
1695 | Values for COMMAND are: | |
1696 | ||
1697 | F_DUPFD duplicate a file descriptor | |
1698 | F_GETFD read the descriptor's close-on-exec flag | |
1699 | F_SETFD set the descriptor's close-on-exec flag to VALUE | |
1700 | F_GETFL read the descriptor's flags, as set on open | |
1701 | F_SETFL set the descriptor's flags, as set on open to VALUE | |
1702 | F_GETOWN return the process ID of a socket's owner, for SIGIO | |
1703 | F_SETOWN set the process that owns a socket to VALUE, for SIGIO | |
1704 | FD_CLOEXEC not sure what this is | |
1705 | ||
1706 | For details, see the documentation for the fcntl system call. | |
1707 | ||
1708 | *** The arguments to `select' have changed, for compatibility with | |
1709 | SCSH. The TIMEOUT parameter may now be non-integral, yielding the | |
1710 | expected behavior. The MILLISECONDS parameter has been changed to | |
1711 | MICROSECONDS, to more closely resemble the underlying system call. | |
1712 | The RVEC, WVEC, and EVEC arguments can now be vectors; the type of the | |
1713 | corresponding return set will be the same. | |
1714 | ||
1715 | *** The arguments to the `mknod' system call have changed. They are | |
1716 | now: | |
1717 | ||
1718 | (mknod PATH TYPE PERMS DEV) | |
1719 | Create a new file (`node') in the file system. PATH is the name of | |
1720 | the file to create. TYPE is the kind of file to create; it should | |
1721 | be 'fifo, 'block-special, or 'char-special. PERMS specifies the | |
1722 | permission bits to give the newly created file. If TYPE is | |
1723 | 'block-special or 'char-special, DEV specifies which device the | |
1724 | special file refers to; its interpretation depends on the kind of | |
1725 | special file being created. | |
1726 | ||
1727 | *** The `fork' function has been renamed to `primitive-fork', to avoid | |
1728 | clashing with various SCSH forks. | |
1729 | ||
1730 | *** The `recv' and `recvfrom' functions have been renamed to `recv!' | |
1731 | and `recvfrom!'. They no longer accept a size for a second argument; | |
1732 | you must pass a string to hold the received value. They no longer | |
1733 | return the buffer. Instead, `recv' returns the length of the message | |
1734 | received, and `recvfrom' returns a pair containing the packet's length | |
1735 | and originating address. | |
1736 | ||
1737 | *** The file descriptor datatype has been removed, as have the | |
1738 | `read-fd', `write-fd', `close', `lseek', and `dup' functions. | |
1739 | We plan to replace these functions with a SCSH-compatible interface. | |
1740 | ||
1741 | *** The `create' function has been removed; it's just a special case | |
1742 | of `open'. | |
1743 | ||
1744 | *** There are new functions to break down process termination status | |
1745 | values. In the descriptions below, STATUS is a value returned by | |
1746 | `waitpid'. | |
1747 | ||
1748 | (status:exit-val STATUS) | |
1749 | If the child process exited normally, this function returns the exit | |
1750 | code for the child process (i.e., the value passed to exit, or | |
1751 | returned from main). If the child process did not exit normally, | |
1752 | this function returns #f. | |
1753 | ||
1754 | (status:stop-sig STATUS) | |
1755 | If the child process was suspended by a signal, this function | |
1756 | returns the signal that suspended the child. Otherwise, it returns | |
1757 | #f. | |
1758 | ||
1759 | (status:term-sig STATUS) | |
1760 | If the child process terminated abnormally, this function returns | |
1761 | the signal that terminated the child. Otherwise, this function | |
1762 | returns false. | |
1763 | ||
1764 | POSIX promises that exactly one of these functions will return true on | |
1765 | a valid STATUS value. | |
1766 | ||
1767 | These functions are compatible with SCSH. | |
1768 | ||
1769 | *** There are new accessors and setters for the broken-out time vectors | |
48d224d7 JB |
1770 | returned by `localtime', `gmtime', and that ilk. They are: |
1771 | ||
1772 | Component Accessor Setter | |
1773 | ========================= ============ ============ | |
1774 | seconds tm:sec set-tm:sec | |
1775 | minutes tm:min set-tm:min | |
1776 | hours tm:hour set-tm:hour | |
1777 | day of the month tm:mday set-tm:mday | |
1778 | month tm:mon set-tm:mon | |
1779 | year tm:year set-tm:year | |
1780 | day of the week tm:wday set-tm:wday | |
1781 | day in the year tm:yday set-tm:yday | |
1782 | daylight saving time tm:isdst set-tm:isdst | |
1783 | GMT offset, seconds tm:gmtoff set-tm:gmtoff | |
1784 | name of time zone tm:zone set-tm:zone | |
1785 | ||
095936d2 JB |
1786 | *** There are new accessors for the vectors returned by `uname', |
1787 | describing the host system: | |
48d224d7 JB |
1788 | |
1789 | Component Accessor | |
1790 | ============================================== ================ | |
1791 | name of the operating system implementation utsname:sysname | |
1792 | network name of this machine utsname:nodename | |
1793 | release level of the operating system utsname:release | |
1794 | version level of the operating system utsname:version | |
1795 | machine hardware platform utsname:machine | |
1796 | ||
095936d2 JB |
1797 | *** There are new accessors for the vectors returned by `getpw', |
1798 | `getpwnam', `getpwuid', and `getpwent', describing entries from the | |
1799 | system's user database: | |
1800 | ||
1801 | Component Accessor | |
1802 | ====================== ================= | |
1803 | user name passwd:name | |
1804 | user password passwd:passwd | |
1805 | user id passwd:uid | |
1806 | group id passwd:gid | |
1807 | real name passwd:gecos | |
1808 | home directory passwd:dir | |
1809 | shell program passwd:shell | |
1810 | ||
1811 | *** There are new accessors for the vectors returned by `getgr', | |
1812 | `getgrnam', `getgrgid', and `getgrent', describing entries from the | |
1813 | system's group database: | |
1814 | ||
1815 | Component Accessor | |
1816 | ======================= ============ | |
1817 | group name group:name | |
1818 | group password group:passwd | |
1819 | group id group:gid | |
1820 | group members group:mem | |
1821 | ||
1822 | *** There are new accessors for the vectors returned by `gethost', | |
1823 | `gethostbyaddr', `gethostbyname', and `gethostent', describing | |
1824 | internet hosts: | |
1825 | ||
1826 | Component Accessor | |
1827 | ========================= =============== | |
1828 | official name of host hostent:name | |
1829 | alias list hostent:aliases | |
1830 | host address type hostent:addrtype | |
1831 | length of address hostent:length | |
1832 | list of addresses hostent:addr-list | |
1833 | ||
1834 | *** There are new accessors for the vectors returned by `getnet', | |
1835 | `getnetbyaddr', `getnetbyname', and `getnetent', describing internet | |
1836 | networks: | |
1837 | ||
1838 | Component Accessor | |
1839 | ========================= =============== | |
1840 | official name of net netent:name | |
1841 | alias list netent:aliases | |
1842 | net number type netent:addrtype | |
1843 | net number netent:net | |
1844 | ||
1845 | *** There are new accessors for the vectors returned by `getproto', | |
1846 | `getprotobyname', `getprotobynumber', and `getprotoent', describing | |
1847 | internet protocols: | |
1848 | ||
1849 | Component Accessor | |
1850 | ========================= =============== | |
1851 | official protocol name protoent:name | |
1852 | alias list protoent:aliases | |
1853 | protocol number protoent:proto | |
1854 | ||
1855 | *** There are new accessors for the vectors returned by `getserv', | |
1856 | `getservbyname', `getservbyport', and `getservent', describing | |
1857 | internet protocols: | |
1858 | ||
1859 | Component Accessor | |
1860 | ========================= =============== | |
1861 | official service name servent:name | |
1862 | alias list servent:aliases | |
1863 | port number servent:port | |
1864 | protocol to use servent:proto | |
1865 | ||
1866 | *** There are new accessors for the sockaddr structures returned by | |
1867 | `accept', `getsockname', `getpeername', `recvfrom!': | |
1868 | ||
1869 | Component Accessor | |
1870 | ======================================== =============== | |
1871 | address format (`family') sockaddr:fam | |
1872 | path, for file domain addresses sockaddr:path | |
1873 | address, for internet domain addresses sockaddr:addr | |
1874 | TCP or UDP port, for internet sockaddr:port | |
1875 | ||
1876 | *** The `getpwent', `getgrent', `gethostent', `getnetent', | |
1877 | `getprotoent', and `getservent' functions now return #f at the end of | |
1878 | the user database. (They used to throw an exception.) | |
1879 | ||
1880 | Note that calling MUMBLEent function is equivalent to calling the | |
1881 | corresponding MUMBLE function with no arguments. | |
1882 | ||
1883 | *** The `setpwent', `setgrent', `sethostent', `setnetent', | |
1884 | `setprotoent', and `setservent' routines now take no arguments. | |
1885 | ||
1886 | *** The `gethost', `getproto', `getnet', and `getserv' functions now | |
1887 | provide more useful information when they throw an exception. | |
1888 | ||
1889 | *** The `lnaof' function has been renamed to `inet-lnaof'. | |
1890 | ||
1891 | *** Guile now claims to have the `current-time' feature. | |
1892 | ||
1893 | *** The `mktime' function now takes an optional second argument ZONE, | |
1894 | giving the time zone to use for the conversion. ZONE should be a | |
1895 | string, in the same format as expected for the "TZ" environment variable. | |
1896 | ||
1897 | *** The `strptime' function now returns a pair (TIME . COUNT), where | |
1898 | TIME is the parsed time as a vector, and COUNT is the number of | |
1899 | characters from the string left unparsed. This function used to | |
1900 | return the remaining characters as a string. | |
1901 | ||
1902 | *** The `gettimeofday' function has replaced the old `time+ticks' function. | |
1903 | The return value is now (SECONDS . MICROSECONDS); the fractional | |
1904 | component is no longer expressed in "ticks". | |
1905 | ||
1906 | *** The `ticks/sec' constant has been removed, in light of the above change. | |
6685dc83 | 1907 | |
ea00ecba MG |
1908 | * Changes to the gh_ interface |
1909 | ||
1910 | ** gh_eval_str() now returns an SCM object which is the result of the | |
1911 | evaluation | |
1912 | ||
aaef0d2a MG |
1913 | ** gh_scm2str() now copies the Scheme data to a caller-provided C |
1914 | array | |
1915 | ||
1916 | ** gh_scm2newstr() now makes a C array, copies the Scheme data to it, | |
1917 | and returns the array | |
1918 | ||
1919 | ** gh_scm2str0() is gone: there is no need to distinguish | |
1920 | null-terminated from non-null-terminated, since gh_scm2newstr() allows | |
1921 | the user to interpret the data both ways. | |
1922 | ||
f3b1485f JB |
1923 | * Changes to the scm_ interface |
1924 | ||
095936d2 JB |
1925 | ** The new function scm_symbol_value0 provides an easy way to get a |
1926 | symbol's value from C code: | |
1927 | ||
1928 | SCM scm_symbol_value0 (char *NAME) | |
1929 | Return the value of the symbol named by the null-terminated string | |
1930 | NAME in the current module. If the symbol named NAME is unbound in | |
1931 | the current module, return SCM_UNDEFINED. | |
1932 | ||
1933 | ** The new function scm_sysintern0 creates new top-level variables, | |
1934 | without assigning them a value. | |
1935 | ||
1936 | SCM scm_sysintern0 (char *NAME) | |
1937 | Create a new Scheme top-level variable named NAME. NAME is a | |
1938 | null-terminated string. Return the variable's value cell. | |
1939 | ||
1940 | ** The function scm_internal_catch is the guts of catch. It handles | |
1941 | all the mechanics of setting up a catch target, invoking the catch | |
1942 | body, and perhaps invoking the handler if the body does a throw. | |
1943 | ||
1944 | The function is designed to be usable from C code, but is general | |
1945 | enough to implement all the semantics Guile Scheme expects from throw. | |
1946 | ||
1947 | TAG is the catch tag. Typically, this is a symbol, but this function | |
1948 | doesn't actually care about that. | |
1949 | ||
1950 | BODY is a pointer to a C function which runs the body of the catch; | |
1951 | this is the code you can throw from. We call it like this: | |
1952 | BODY (BODY_DATA, JMPBUF) | |
1953 | where: | |
1954 | BODY_DATA is just the BODY_DATA argument we received; we pass it | |
1955 | through to BODY as its first argument. The caller can make | |
1956 | BODY_DATA point to anything useful that BODY might need. | |
1957 | JMPBUF is the Scheme jmpbuf object corresponding to this catch, | |
1958 | which we have just created and initialized. | |
1959 | ||
1960 | HANDLER is a pointer to a C function to deal with a throw to TAG, | |
1961 | should one occur. We call it like this: | |
1962 | HANDLER (HANDLER_DATA, THROWN_TAG, THROW_ARGS) | |
1963 | where | |
1964 | HANDLER_DATA is the HANDLER_DATA argument we recevied; it's the | |
1965 | same idea as BODY_DATA above. | |
1966 | THROWN_TAG is the tag that the user threw to; usually this is | |
1967 | TAG, but it could be something else if TAG was #t (i.e., a | |
1968 | catch-all), or the user threw to a jmpbuf. | |
1969 | THROW_ARGS is the list of arguments the user passed to the THROW | |
1970 | function. | |
1971 | ||
1972 | BODY_DATA is just a pointer we pass through to BODY. HANDLER_DATA | |
1973 | is just a pointer we pass through to HANDLER. We don't actually | |
1974 | use either of those pointers otherwise ourselves. The idea is | |
1975 | that, if our caller wants to communicate something to BODY or | |
1976 | HANDLER, it can pass a pointer to it as MUMBLE_DATA, which BODY and | |
1977 | HANDLER can then use. Think of it as a way to make BODY and | |
1978 | HANDLER closures, not just functions; MUMBLE_DATA points to the | |
1979 | enclosed variables. | |
1980 | ||
1981 | Of course, it's up to the caller to make sure that any data a | |
1982 | MUMBLE_DATA needs is protected from GC. A common way to do this is | |
1983 | to make MUMBLE_DATA a pointer to data stored in an automatic | |
1984 | structure variable; since the collector must scan the stack for | |
1985 | references anyway, this assures that any references in MUMBLE_DATA | |
1986 | will be found. | |
1987 | ||
1988 | ** The new function scm_internal_lazy_catch is exactly like | |
1989 | scm_internal_catch, except: | |
1990 | ||
1991 | - It does not unwind the stack (this is the major difference). | |
1992 | - If handler returns, its value is returned from the throw. | |
1993 | - BODY always receives #f as its JMPBUF argument (since there's no | |
1994 | jmpbuf associated with a lazy catch, because we don't unwind the | |
1995 | stack.) | |
1996 | ||
1997 | ** scm_body_thunk is a new body function you can pass to | |
1998 | scm_internal_catch if you want the body to be like Scheme's `catch' | |
1999 | --- a thunk, or a function of one argument if the tag is #f. | |
2000 | ||
2001 | BODY_DATA is a pointer to a scm_body_thunk_data structure, which | |
2002 | contains the Scheme procedure to invoke as the body, and the tag | |
2003 | we're catching. If the tag is #f, then we pass JMPBUF (created by | |
2004 | scm_internal_catch) to the body procedure; otherwise, the body gets | |
2005 | no arguments. | |
2006 | ||
2007 | ** scm_handle_by_proc is a new handler function you can pass to | |
2008 | scm_internal_catch if you want the handler to act like Scheme's catch | |
2009 | --- call a procedure with the tag and the throw arguments. | |
2010 | ||
2011 | If the user does a throw to this catch, this function runs a handler | |
2012 | procedure written in Scheme. HANDLER_DATA is a pointer to an SCM | |
2013 | variable holding the Scheme procedure object to invoke. It ought to | |
2014 | be a pointer to an automatic variable (i.e., one living on the stack), | |
2015 | or the procedure object should be otherwise protected from GC. | |
2016 | ||
2017 | ** scm_handle_by_message is a new handler function to use with | |
2018 | `scm_internal_catch' if you want Guile to print a message and die. | |
2019 | It's useful for dealing with throws to uncaught keys at the top level. | |
2020 | ||
2021 | HANDLER_DATA, if non-zero, is assumed to be a char * pointing to a | |
2022 | message header to print; if zero, we use "guile" instead. That | |
2023 | text is followed by a colon, then the message described by ARGS. | |
2024 | ||
2025 | ** The return type of scm_boot_guile is now void; the function does | |
2026 | not return a value, and indeed, never returns at all. | |
2027 | ||
f3b1485f JB |
2028 | ** The new function scm_shell makes it easy for user applications to |
2029 | process command-line arguments in a way that is compatible with the | |
2030 | stand-alone guile interpreter (which is in turn compatible with SCSH, | |
2031 | the Scheme shell). | |
2032 | ||
2033 | To use the scm_shell function, first initialize any guile modules | |
2034 | linked into your application, and then call scm_shell with the values | |
7ed46dc8 | 2035 | of ARGC and ARGV your `main' function received. scm_shell will add |
f3b1485f JB |
2036 | any SCSH-style meta-arguments from the top of the script file to the |
2037 | argument vector, and then process the command-line arguments. This | |
2038 | generally means loading a script file or starting up an interactive | |
2039 | command interpreter. For details, see "Changes to the stand-alone | |
2040 | interpreter" above. | |
2041 | ||
095936d2 JB |
2042 | ** The new functions scm_get_meta_args and scm_count_argv help you |
2043 | implement the SCSH-style meta-argument, `\'. | |
2044 | ||
2045 | char **scm_get_meta_args (int ARGC, char **ARGV) | |
2046 | If the second element of ARGV is a string consisting of a single | |
2047 | backslash character (i.e. "\\" in Scheme notation), open the file | |
2048 | named by the following argument, parse arguments from it, and return | |
2049 | the spliced command line. The returned array is terminated by a | |
2050 | null pointer. | |
2051 | ||
2052 | For details of argument parsing, see above, under "guile now accepts | |
2053 | command-line arguments compatible with SCSH..." | |
2054 | ||
2055 | int scm_count_argv (char **ARGV) | |
2056 | Count the arguments in ARGV, assuming it is terminated by a null | |
2057 | pointer. | |
2058 | ||
2059 | For an example of how these functions might be used, see the source | |
2060 | code for the function scm_shell in libguile/script.c. | |
2061 | ||
2062 | You will usually want to use scm_shell instead of calling this | |
2063 | function yourself. | |
2064 | ||
2065 | ** The new function scm_compile_shell_switches turns an array of | |
2066 | command-line arguments into Scheme code to carry out the actions they | |
2067 | describe. Given ARGC and ARGV, it returns a Scheme expression to | |
2068 | evaluate, and calls scm_set_program_arguments to make any remaining | |
2069 | command-line arguments available to the Scheme code. For example, | |
2070 | given the following arguments: | |
2071 | ||
2072 | -e main -s ekko a speckled gecko | |
2073 | ||
2074 | scm_set_program_arguments will return the following expression: | |
2075 | ||
2076 | (begin (load "ekko") (main (command-line)) (quit)) | |
2077 | ||
2078 | You will usually want to use scm_shell instead of calling this | |
2079 | function yourself. | |
2080 | ||
2081 | ** The function scm_shell_usage prints a usage message appropriate for | |
2082 | an interpreter that uses scm_compile_shell_switches to handle its | |
2083 | command-line arguments. | |
2084 | ||
2085 | void scm_shell_usage (int FATAL, char *MESSAGE) | |
2086 | Print a usage message to the standard error output. If MESSAGE is | |
2087 | non-zero, write it before the usage message, followed by a newline. | |
2088 | If FATAL is non-zero, exit the process, using FATAL as the | |
2089 | termination status. (If you want to be compatible with Guile, | |
2090 | always use 1 as the exit status when terminating due to command-line | |
2091 | usage problems.) | |
2092 | ||
2093 | You will usually want to use scm_shell instead of calling this | |
2094 | function yourself. | |
48d224d7 JB |
2095 | |
2096 | ** scm_eval_0str now returns SCM_UNSPECIFIED if the string contains no | |
095936d2 JB |
2097 | expressions. It used to return SCM_EOL. Earth-shattering. |
2098 | ||
2099 | ** The macros for declaring scheme objects in C code have been | |
2100 | rearranged slightly. They are now: | |
2101 | ||
2102 | SCM_SYMBOL (C_NAME, SCHEME_NAME) | |
2103 | Declare a static SCM variable named C_NAME, and initialize it to | |
2104 | point to the Scheme symbol whose name is SCHEME_NAME. C_NAME should | |
2105 | be a C identifier, and SCHEME_NAME should be a C string. | |
2106 | ||
2107 | SCM_GLOBAL_SYMBOL (C_NAME, SCHEME_NAME) | |
2108 | Just like SCM_SYMBOL, but make C_NAME globally visible. | |
2109 | ||
2110 | SCM_VCELL (C_NAME, SCHEME_NAME) | |
2111 | Create a global variable at the Scheme level named SCHEME_NAME. | |
2112 | Declare a static SCM variable named C_NAME, and initialize it to | |
2113 | point to the Scheme variable's value cell. | |
2114 | ||
2115 | SCM_GLOBAL_VCELL (C_NAME, SCHEME_NAME) | |
2116 | Just like SCM_VCELL, but make C_NAME globally visible. | |
2117 | ||
2118 | The `guile-snarf' script writes initialization code for these macros | |
2119 | to its standard output, given C source code as input. | |
2120 | ||
2121 | The SCM_GLOBAL macro is gone. | |
2122 | ||
2123 | ** The scm_read_line and scm_read_line_x functions have been replaced | |
2124 | by Scheme code based on the %read-delimited! procedure (known to C | |
2125 | code as scm_read_delimited_x). See its description above for more | |
2126 | information. | |
48d224d7 | 2127 | |
095936d2 JB |
2128 | ** The function scm_sys_open has been renamed to scm_open. It now |
2129 | returns a port instead of an FD object. | |
ea00ecba | 2130 | |
095936d2 JB |
2131 | * The dynamic linking support has changed. For more information, see |
2132 | libguile/DYNAMIC-LINKING. | |
ea00ecba | 2133 | |
f7b47737 JB |
2134 | \f |
2135 | Guile 1.0b3 | |
3065a62a | 2136 | |
f3b1485f JB |
2137 | User-visible changes from Thursday, September 5, 1996 until Guile 1.0 |
2138 | (Sun 5 Jan 1997): | |
3065a62a | 2139 | |
4b521edb | 2140 | * Changes to the 'guile' program: |
3065a62a | 2141 | |
4b521edb JB |
2142 | ** Guile now loads some new files when it starts up. Guile first |
2143 | searches the load path for init.scm, and loads it if found. Then, if | |
2144 | Guile is not being used to execute a script, and the user's home | |
2145 | directory contains a file named `.guile', Guile loads that. | |
c6486f8a | 2146 | |
4b521edb | 2147 | ** You can now use Guile as a shell script interpreter. |
3065a62a JB |
2148 | |
2149 | To paraphrase the SCSH manual: | |
2150 | ||
2151 | When Unix tries to execute an executable file whose first two | |
2152 | characters are the `#!', it treats the file not as machine code to | |
2153 | be directly executed by the native processor, but as source code | |
2154 | to be executed by some interpreter. The interpreter to use is | |
2155 | specified immediately after the #! sequence on the first line of | |
2156 | the source file. The kernel reads in the name of the interpreter, | |
2157 | and executes that instead. It passes the interpreter the source | |
2158 | filename as its first argument, with the original arguments | |
2159 | following. Consult the Unix man page for the `exec' system call | |
2160 | for more information. | |
2161 | ||
1a1945be JB |
2162 | Now you can use Guile as an interpreter, using a mechanism which is a |
2163 | compatible subset of that provided by SCSH. | |
2164 | ||
3065a62a JB |
2165 | Guile now recognizes a '-s' command line switch, whose argument is the |
2166 | name of a file of Scheme code to load. It also treats the two | |
2167 | characters `#!' as the start of a comment, terminated by `!#'. Thus, | |
2168 | to make a file of Scheme code directly executable by Unix, insert the | |
2169 | following two lines at the top of the file: | |
2170 | ||
2171 | #!/usr/local/bin/guile -s | |
2172 | !# | |
2173 | ||
2174 | Guile treats the argument of the `-s' command-line switch as the name | |
2175 | of a file of Scheme code to load, and treats the sequence `#!' as the | |
2176 | start of a block comment, terminated by `!#'. | |
2177 | ||
2178 | For example, here's a version of 'echo' written in Scheme: | |
2179 | ||
2180 | #!/usr/local/bin/guile -s | |
2181 | !# | |
2182 | (let loop ((args (cdr (program-arguments)))) | |
2183 | (if (pair? args) | |
2184 | (begin | |
2185 | (display (car args)) | |
2186 | (if (pair? (cdr args)) | |
2187 | (display " ")) | |
2188 | (loop (cdr args))))) | |
2189 | (newline) | |
2190 | ||
2191 | Why does `#!' start a block comment terminated by `!#', instead of the | |
2192 | end of the line? That is the notation SCSH uses, and although we | |
2193 | don't yet support the other SCSH features that motivate that choice, | |
2194 | we would like to be backward-compatible with any existing Guile | |
3763761c JB |
2195 | scripts once we do. Furthermore, if the path to Guile on your system |
2196 | is too long for your kernel, you can start the script with this | |
2197 | horrible hack: | |
2198 | ||
2199 | #!/bin/sh | |
2200 | exec /really/long/path/to/guile -s "$0" ${1+"$@"} | |
2201 | !# | |
3065a62a JB |
2202 | |
2203 | Note that some very old Unix systems don't support the `#!' syntax. | |
2204 | ||
c6486f8a | 2205 | |
4b521edb | 2206 | ** You can now run Guile without installing it. |
6685dc83 JB |
2207 | |
2208 | Previous versions of the interactive Guile interpreter (`guile') | |
2209 | couldn't start up unless Guile's Scheme library had been installed; | |
2210 | they used the value of the environment variable `SCHEME_LOAD_PATH' | |
2211 | later on in the startup process, but not to find the startup code | |
2212 | itself. Now Guile uses `SCHEME_LOAD_PATH' in all searches for Scheme | |
2213 | code. | |
2214 | ||
2215 | To run Guile without installing it, build it in the normal way, and | |
2216 | then set the environment variable `SCHEME_LOAD_PATH' to a | |
2217 | colon-separated list of directories, including the top-level directory | |
2218 | of the Guile sources. For example, if you unpacked Guile so that the | |
2219 | full filename of this NEWS file is /home/jimb/guile-1.0b3/NEWS, then | |
2220 | you might say | |
2221 | ||
2222 | export SCHEME_LOAD_PATH=/home/jimb/my-scheme:/home/jimb/guile-1.0b3 | |
2223 | ||
c6486f8a | 2224 | |
4b521edb JB |
2225 | ** Guile's read-eval-print loop no longer prints #<unspecified> |
2226 | results. If the user wants to see this, she can evaluate the | |
2227 | expression (assert-repl-print-unspecified #t), perhaps in her startup | |
48d224d7 | 2228 | file. |
6685dc83 | 2229 | |
4b521edb JB |
2230 | ** Guile no longer shows backtraces by default when an error occurs; |
2231 | however, it does display a message saying how to get one, and how to | |
2232 | request that they be displayed by default. After an error, evaluate | |
2233 | (backtrace) | |
2234 | to see a backtrace, and | |
2235 | (debug-enable 'backtrace) | |
2236 | to see them by default. | |
6685dc83 | 2237 | |
6685dc83 | 2238 | |
d9fb83d9 | 2239 | |
4b521edb JB |
2240 | * Changes to Guile Scheme: |
2241 | ||
2242 | ** Guile now distinguishes between #f and the empty list. | |
2243 | ||
2244 | This is for compatibility with the IEEE standard, the (possibly) | |
2245 | upcoming Revised^5 Report on Scheme, and many extant Scheme | |
2246 | implementations. | |
2247 | ||
2248 | Guile used to have #f and '() denote the same object, to make Scheme's | |
2249 | type system more compatible with Emacs Lisp's. However, the change | |
2250 | caused too much trouble for Scheme programmers, and we found another | |
2251 | way to reconcile Emacs Lisp with Scheme that didn't require this. | |
2252 | ||
2253 | ||
2254 | ** Guile's delq, delv, delete functions, and their destructive | |
c6486f8a JB |
2255 | counterparts, delq!, delv!, and delete!, now remove all matching |
2256 | elements from the list, not just the first. This matches the behavior | |
2257 | of the corresponding Emacs Lisp functions, and (I believe) the Maclisp | |
2258 | functions which inspired them. | |
2259 | ||
2260 | I recognize that this change may break code in subtle ways, but it | |
2261 | seems best to make the change before the FSF's first Guile release, | |
2262 | rather than after. | |
2263 | ||
2264 | ||
4b521edb | 2265 | ** The compiled-library-path function has been deleted from libguile. |
6685dc83 | 2266 | |
4b521edb | 2267 | ** The facilities for loading Scheme source files have changed. |
c6486f8a | 2268 | |
4b521edb | 2269 | *** The variable %load-path now tells Guile which directories to search |
6685dc83 JB |
2270 | for Scheme code. Its value is a list of strings, each of which names |
2271 | a directory. | |
2272 | ||
4b521edb JB |
2273 | *** The variable %load-extensions now tells Guile which extensions to |
2274 | try appending to a filename when searching the load path. Its value | |
2275 | is a list of strings. Its default value is ("" ".scm"). | |
2276 | ||
2277 | *** (%search-load-path FILENAME) searches the directories listed in the | |
2278 | value of the %load-path variable for a Scheme file named FILENAME, | |
2279 | with all the extensions listed in %load-extensions. If it finds a | |
2280 | match, then it returns its full filename. If FILENAME is absolute, it | |
2281 | returns it unchanged. Otherwise, it returns #f. | |
6685dc83 | 2282 | |
4b521edb JB |
2283 | %search-load-path will not return matches that refer to directories. |
2284 | ||
2285 | *** (primitive-load FILENAME :optional CASE-INSENSITIVE-P SHARP) | |
2286 | uses %seach-load-path to find a file named FILENAME, and loads it if | |
2287 | it finds it. If it can't read FILENAME for any reason, it throws an | |
2288 | error. | |
6685dc83 JB |
2289 | |
2290 | The arguments CASE-INSENSITIVE-P and SHARP are interpreted as by the | |
4b521edb JB |
2291 | `read' function. |
2292 | ||
2293 | *** load uses the same searching semantics as primitive-load. | |
2294 | ||
2295 | *** The functions %try-load, try-load-with-path, %load, load-with-path, | |
2296 | basic-try-load-with-path, basic-load-with-path, try-load-module-with- | |
2297 | path, and load-module-with-path have been deleted. The functions | |
2298 | above should serve their purposes. | |
2299 | ||
2300 | *** If the value of the variable %load-hook is a procedure, | |
2301 | `primitive-load' applies its value to the name of the file being | |
2302 | loaded (without the load path directory name prepended). If its value | |
2303 | is #f, it is ignored. Otherwise, an error occurs. | |
2304 | ||
2305 | This is mostly useful for printing load notification messages. | |
2306 | ||
2307 | ||
2308 | ** The function `eval!' is no longer accessible from the scheme level. | |
2309 | We can't allow operations which introduce glocs into the scheme level, | |
2310 | because Guile's type system can't handle these as data. Use `eval' or | |
2311 | `read-and-eval!' (see below) as replacement. | |
2312 | ||
2313 | ** The new function read-and-eval! reads an expression from PORT, | |
2314 | evaluates it, and returns the result. This is more efficient than | |
2315 | simply calling `read' and `eval', since it is not necessary to make a | |
2316 | copy of the expression for the evaluator to munge. | |
2317 | ||
2318 | Its optional arguments CASE_INSENSITIVE_P and SHARP are interpreted as | |
2319 | for the `read' function. | |
2320 | ||
2321 | ||
2322 | ** The function `int?' has been removed; its definition was identical | |
2323 | to that of `integer?'. | |
2324 | ||
2325 | ** The functions `<?', `<?', `<=?', `=?', `>?', and `>=?'. Code should | |
2326 | use the R4RS names for these functions. | |
2327 | ||
2328 | ** The function object-properties no longer returns the hash handle; | |
2329 | it simply returns the object's property list. | |
2330 | ||
2331 | ** Many functions have been changed to throw errors, instead of | |
2332 | returning #f on failure. The point of providing exception handling in | |
2333 | the language is to simplify the logic of user code, but this is less | |
2334 | useful if Guile's primitives don't throw exceptions. | |
2335 | ||
2336 | ** The function `fileno' has been renamed from `%fileno'. | |
2337 | ||
2338 | ** The function primitive-mode->fdes returns #t or #f now, not 1 or 0. | |
2339 | ||
2340 | ||
2341 | * Changes to Guile's C interface: | |
2342 | ||
2343 | ** The library's initialization procedure has been simplified. | |
2344 | scm_boot_guile now has the prototype: | |
2345 | ||
2346 | void scm_boot_guile (int ARGC, | |
2347 | char **ARGV, | |
2348 | void (*main_func) (), | |
2349 | void *closure); | |
2350 | ||
2351 | scm_boot_guile calls MAIN_FUNC, passing it CLOSURE, ARGC, and ARGV. | |
2352 | MAIN_FUNC should do all the work of the program (initializing other | |
2353 | packages, reading user input, etc.) before returning. When MAIN_FUNC | |
2354 | returns, call exit (0); this function never returns. If you want some | |
2355 | other exit value, MAIN_FUNC may call exit itself. | |
2356 | ||
2357 | scm_boot_guile arranges for program-arguments to return the strings | |
2358 | given by ARGC and ARGV. If MAIN_FUNC modifies ARGC/ARGV, should call | |
2359 | scm_set_program_arguments with the final list, so Scheme code will | |
2360 | know which arguments have been processed. | |
2361 | ||
2362 | scm_boot_guile establishes a catch-all catch handler which prints an | |
2363 | error message and exits the process. This means that Guile exits in a | |
2364 | coherent way when system errors occur and the user isn't prepared to | |
2365 | handle it. If the user doesn't like this behavior, they can establish | |
2366 | their own universal catcher in MAIN_FUNC to shadow this one. | |
2367 | ||
2368 | Why must the caller do all the real work from MAIN_FUNC? The garbage | |
2369 | collector assumes that all local variables of type SCM will be above | |
2370 | scm_boot_guile's stack frame on the stack. If you try to manipulate | |
2371 | SCM values after this function returns, it's the luck of the draw | |
2372 | whether the GC will be able to find the objects you allocate. So, | |
2373 | scm_boot_guile function exits, rather than returning, to discourage | |
2374 | people from making that mistake. | |
2375 | ||
2376 | The IN, OUT, and ERR arguments were removed; there are other | |
2377 | convenient ways to override these when desired. | |
2378 | ||
2379 | The RESULT argument was deleted; this function should never return. | |
2380 | ||
2381 | The BOOT_CMD argument was deleted; the MAIN_FUNC argument is more | |
2382 | general. | |
2383 | ||
2384 | ||
2385 | ** Guile's header files should no longer conflict with your system's | |
2386 | header files. | |
2387 | ||
2388 | In order to compile code which #included <libguile.h>, previous | |
2389 | versions of Guile required you to add a directory containing all the | |
2390 | Guile header files to your #include path. This was a problem, since | |
2391 | Guile's header files have names which conflict with many systems' | |
2392 | header files. | |
2393 | ||
2394 | Now only <libguile.h> need appear in your #include path; you must | |
2395 | refer to all Guile's other header files as <libguile/mumble.h>. | |
2396 | Guile's installation procedure puts libguile.h in $(includedir), and | |
2397 | the rest in $(includedir)/libguile. | |
2398 | ||
2399 | ||
2400 | ** Two new C functions, scm_protect_object and scm_unprotect_object, | |
2401 | have been added to the Guile library. | |
2402 | ||
2403 | scm_protect_object (OBJ) protects OBJ from the garbage collector. | |
2404 | OBJ will not be freed, even if all other references are dropped, | |
2405 | until someone does scm_unprotect_object (OBJ). Both functions | |
2406 | return OBJ. | |
2407 | ||
2408 | Note that calls to scm_protect_object do not nest. You can call | |
2409 | scm_protect_object any number of times on a given object, and the | |
2410 | next call to scm_unprotect_object will unprotect it completely. | |
2411 | ||
2412 | Basically, scm_protect_object and scm_unprotect_object just | |
2413 | maintain a list of references to things. Since the GC knows about | |
2414 | this list, all objects it mentions stay alive. scm_protect_object | |
2415 | adds its argument to the list; scm_unprotect_object remove its | |
2416 | argument from the list. | |
2417 | ||
2418 | ||
2419 | ** scm_eval_0str now returns the value of the last expression | |
2420 | evaluated. | |
2421 | ||
2422 | ** The new function scm_read_0str reads an s-expression from a | |
2423 | null-terminated string, and returns it. | |
2424 | ||
2425 | ** The new function `scm_stdio_to_port' converts a STDIO file pointer | |
2426 | to a Scheme port object. | |
2427 | ||
2428 | ** The new function `scm_set_program_arguments' allows C code to set | |
e80c8fea | 2429 | the value returned by the Scheme `program-arguments' function. |
6685dc83 | 2430 | |
6685dc83 | 2431 | \f |
1a1945be JB |
2432 | Older changes: |
2433 | ||
2434 | * Guile no longer includes sophisticated Tcl/Tk support. | |
2435 | ||
2436 | The old Tcl/Tk support was unsatisfying to us, because it required the | |
2437 | user to link against the Tcl library, as well as Tk and Guile. The | |
2438 | interface was also un-lispy, in that it preserved Tcl/Tk's practice of | |
2439 | referring to widgets by names, rather than exporting widgets to Scheme | |
2440 | code as a special datatype. | |
2441 | ||
2442 | In the Usenix Tk Developer's Workshop held in July 1996, the Tcl/Tk | |
2443 | maintainers described some very interesting changes in progress to the | |
2444 | Tcl/Tk internals, which would facilitate clean interfaces between lone | |
2445 | Tk and other interpreters --- even for garbage-collected languages | |
2446 | like Scheme. They expected the new Tk to be publicly available in the | |
2447 | fall of 1996. | |
2448 | ||
2449 | Since it seems that Guile might soon have a new, cleaner interface to | |
2450 | lone Tk, and that the old Guile/Tk glue code would probably need to be | |
2451 | completely rewritten, we (Jim Blandy and Richard Stallman) have | |
2452 | decided not to support the old code. We'll spend the time instead on | |
2453 | a good interface to the newer Tk, as soon as it is available. | |
5c54da76 | 2454 | |
8512dea6 | 2455 | Until then, gtcltk-lib provides trivial, low-maintenance functionality. |
deb95d71 | 2456 | |
5c54da76 JB |
2457 | \f |
2458 | Copyright information: | |
2459 | ||
ea00ecba | 2460 | Copyright (C) 1996,1997 Free Software Foundation, Inc. |
5c54da76 JB |
2461 | |
2462 | Permission is granted to anyone to make or distribute verbatim copies | |
2463 | of this document as received, in any medium, provided that the | |
2464 | copyright notice and this permission notice are preserved, | |
2465 | thus giving the recipient permission to redistribute in turn. | |
2466 | ||
2467 | Permission is granted to distribute modified versions | |
2468 | of this document, or of portions of it, | |
2469 | under the above conditions, provided also that they | |
2470 | carry prominent notices stating who last changed them. | |
2471 | ||
48d224d7 JB |
2472 | \f |
2473 | Local variables: | |
2474 | mode: outline | |
2475 | paragraph-separate: "[ \f]*$" | |
2476 | end: | |
2477 |