Date: Tue, 4 Jun 1996 08:34:28 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Robert Jaycocks <r DOT jaycocks1 AT lut DOT ac DOT uk>
Cc: djgpp AT delorie DOT com
Subject: Re: Emacs19.31
In-Reply-To: <31B285E3.2769@lut.ac.uk>
Message-Id: <Pine.SUN.3.91.960604082608.23408D-100000@is>
Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII


On Mon, 3 Jun 1996, Robert Jaycocks wrote:

> Has anyone managed to get emacs19.31 compiled under DJGPPv2. I've 
> compiled it, but for some reason the Shell command is not working.
> When I perform a Shell command (using ESC !), the following is
> printed in the mini-buffer
> 
> Searching for program: permission denied (EACCES), c:/command.com

This is due to a bug in the library function `_is_executable' which was
reported a couple of months ago to the DJGPP bug-tracking system.  To
correct it, apply the patch below to the file
src/libc/posix/sys/stat/is_exec.c, compile it and put it into libc.a; 
then rebuild Emacs.

There is one other library bug that should be visible when linking Emacs 
19.31 with stock libc.a: after you shell to DOS, Ctrl-Break kills Emacs.  
Below I attach a patch to the library function `sigaction' that should 
correct this problem.

*** posix/sys/stat/is_exec.c~0	Sun Nov 12 23:22:48 1995
--- posix/sys/stat/is_exec.c	Sat Apr  6 13:09:48 1996
***************
*** 18,23 ****
--- 18,24 ----
  #include <libc/stubs.h>
  #include <stdio.h>
  #include <string.h>
+ #include <ctype.h>
  #include <errno.h>
  #include <dpmi.h>
  #include <go32.h>
***************
*** 182,192 ****
        && strlen(extension) <= ((extension[0]=='.') ? 4 : 3))
      {
        /* Search the list of extensions in executables[]. */
!       char tmp_buf[6];
  
!       tmp_buf[0] = '|';
!       strcpy(tmp_buf+1, *extension == '.' ? extension + 1 : extension);
!       strcat(tmp_buf, "|");
        if (strstr(non_executables, tmp_buf))
          return 0;
        else if (strstr(executables, tmp_buf))
--- 183,197 ----
        && strlen(extension) <= ((extension[0]=='.') ? 4 : 3))
      {
        /* Search the list of extensions in executables[]. */
!       char tmp_buf[6], *tp = tmp_buf;
  
!       *tp++ = '|';
!       if (*extension == '.')
! 	extension++;
!       while (*extension)
! 	*tp++ = toupper (*extension++);
!       *tp++ = '|';
!       *tp = '\0';
        if (strstr(non_executables, tmp_buf))
          return 0;
        else if (strstr(executables, tmp_buf))

*** posix/signal/sigactio.c~0	Sun Apr  2 01:11:10 1995
--- posix/signal/sigactio.c	Thu Apr  4 19:50:18 1996
***************
*** 1,19 ****
  /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */
  #include <signal.h>
  
  int
  sigaction(int _sig, const struct sigaction *_act, struct sigaction *_oact)
  {
    if (_oact)
    {
      /* FIXME */
!     _oact->sa_handler = SIG_DFL;
!     sigemptyset(&_oact->sa_mask);
      _oact->sa_flags = 0;
    }
    if (_act)
    {
!     signal(_sig, _act->sa_handler);
    }
!   return 0;
  }
--- 1,35 ----
  /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */
  #include <signal.h>
+ #include <errno.h>
  
  int
  sigaction(int _sig, const struct sigaction *_act, struct sigaction *_oact)
  {
+   int retval = 0;
+ 
    if (_oact)
    {
+     void (*installed_sig)(int) = signal (_sig, SIG_IGN);
+ 
      /* FIXME */
!     if (installed_sig == SIG_ERR)
!     {
!       retval = -1;
!       errno = EINVAL;
!     }
!     else
!       signal (_sig, installed_sig);
!     _oact->sa_handler = installed_sig;
!     retval = sigemptyset(&_oact->sa_mask);
      _oact->sa_flags = 0;
    }
    if (_act)
    {
!     if (signal(_sig, _act->sa_handler) == SIG_ERR)
!     {
!       retval = -1;
!       errno = EINVAL;
!     }
    }
!   return retval;
  }