1999-07-13 Gary Houston <ghouston@easynet.co.uk>

1999-07-13  Gary Houston  <ghouston@easynet.co.uk>
	* strports.c (scm_strprint_obj): simplify.  start with initial
	buffer size of 0.
	(st_seek): don't allow string to be extended if seeking past
	the end of a read-only port.
1999-07-12  Gary Houston  <ghouston@easynet.co.uk>
	* strports.c (st_seek): change the resize checks.
	* ports.c (scm_ftruncate): throw error if offset works out negative.
	* strports.c (st_flush): increase string size in blocks of
	SCM_WRITE_BLOCK instead of 1. set read_end to read_pos if
	it's greater and reset read_buf_size.
	(scm_mkstrport): set rw_randow if only writing, since read_buf needs
	to be maintained for output ports too (it holds the written
	part of the string, while write_buf may have unwritten buffer
	chars.)
	(st_truncate): rewritten.
	(top of file): added a few notes.
1999-07-06  Gary Houston  <ghouston@easynet.co.uk>
	* strports.c (st_grow_port): set pt->read_pos.  set
	pt->read_buf_size one less than pt->write_buf_size if there's
	an unwritten char at the end of the string.  similarly for
	pt->read_end.
	(st_resize_port): renamed from st_grow_port.
	(st_seek): simplify by assuming that pt->write_pos == pt->read_pos.
	seek from read_end instead of write_end for SEEK_END.
	(st_ftruncate): calculate current length using readbuf, not write
	buf.
	(scm_strport_to_string): use read_buf_size for length.
	(stfill_buffer): don't re-initialise the readbuf.
1999-07-05  Gary Houston  <ghouston@easynet.co.uk>
	* strports.c (scm_strport_to_string): new procedure.
	(scm_call_with_output_string, scm_strprint_obj): use
	scm_strport_to_string.
	used SCM_INUM0 instead of SCM_MAKINUM (0) in a few places.