A few more bugfixes and new features.

A few more bugfixes and new features.

(Sigh.)  I obviously need to remember to separate individual changes
to multiple commits.

src/emacsclient.c: Improved error handling.
(decode_options): Changed frame option (again) from -f to -t.
(print_help_and_exit): Ditto.
(copy_from_to): Check EINTR after write, not EAGAIN.  Removed SIGIO hack.
(pty_conversation): Handle errors transmitted through the socket.
Handle pty errors by not reading from it anymore.
(main): Restore correct errno after socket_status failed.  Send -tty
on -t, not -pty.

lisp/server.el (server-process-filter): Watch -tty, not -pty.
Use make-frame-on-tty instead of make-terminal-frame.
Don't set newframe to t if make-frame-on-tty failed.
Don't delete frames here.  Print correct message when there are no
files to edit, but a new frame was requested.
(server-sentinel): Delete the frame after the process.
(server-handle-delete-frame): New function for delete-frame-functions.
(server-start): Add server-handle-delete-frame to delete-frame-functions.
(server-buffer-done): Don't delete frames here.

src/alloc.c (mark_ttys): Add prototype.
(Fgarbage_collect): Call mark_ttys.

src/emacs.c: (shut_down_emacs): Don't flush stdout before
reset_sys_modes().

src/process.c (add_keyboard_wait_descriptor_called_flag): Removed.
(add_keyboard_wait_descriptor): Removed stdin hack.

src/sysdep.c: Unconditionally include sysselect.h.
(old_fcntl_flags): Changed to an array.
(init_sigio, reset_sigio): Use it.
(narrow_foreground_group, widen_foreground_group): Use setpgid, not
setpgrp.
(old_fcntl_owner): Changed to an array.
(init_sys_modes, reset_sys_modes): Use it.  Fix fsync() and reset_sigio() calls.
src/term.c (Qframe_tty_name, Qframe_tty_type): New variables.
(syms_of_term): Initialize them.
(Fframe_tty_name, Fframe_tty_type): New functions.
(term_init): Call add_keyboard_wait_descriptor().
(Fdelete_tty): New function.
(delete_tty): Call delete_keyboard_wait_descriptor().
(get_current_tty): Removed.
(mark_ttys): New function.

git-archimport-id: lorentey@elte.hu--2004/emacs--multi-tty--0--patch-28