1 /* Synchronous subprocess invocation for GNU Emacs.
2 Copyright (C) 1985-1988, 1993-1995, 1999-2012
3 Free Software Foundation, Inc.
5 This file is part of GNU Emacs.
7 GNU Emacs is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 GNU Emacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
24 #include <sys/types.h>
36 #define _P_NOWAIT 1 /* from process.h */
39 #ifdef MSDOS /* Demacs 1.1.1 91/10/16 HIRANO Satoshi */
41 #include <sys/param.h>
45 #include "character.h"
49 #include "composite.h"
52 #include "syssignal.h"
55 #include "blockinput.h"
57 #include "termhooks.h"
67 /* Pattern used by call-process-region to make temp files. */
68 static Lisp_Object Vtemp_file_name_pattern
;
70 /* True if we are about to fork off a synchronous process or if we
71 are waiting for it. */
72 bool synch_process_alive
;
74 /* Nonzero => this is a string explaining death of synchronous subprocess. */
75 const char *synch_process_death
;
77 /* Nonzero => this is the signal number that terminated the subprocess. */
78 int synch_process_termsig
;
80 /* If synch_process_death is zero,
81 this is exit code of synchronous subprocess. */
82 int synch_process_retcode
;
85 /* Clean up when exiting Fcall_process.
86 On MSDOS, delete the temporary file on any kind of termination.
87 On Unix, kill the process and any children on termination by signal. */
89 /* True if this is termination due to exit. */
90 static bool call_process_exited
;
93 call_process_kill (Lisp_Object fdpid
)
97 CONS_TO_INTEGER (Fcar (fdpid
), int, fd
);
98 CONS_TO_INTEGER (Fcdr (fdpid
), pid_t
, pid
);
100 EMACS_KILLPG (pid
, SIGKILL
);
101 synch_process_alive
= 0;
106 call_process_cleanup (Lisp_Object arg
)
108 Lisp_Object fdpid
= Fcdr (arg
);
116 Fset_buffer (Fcar (arg
));
117 CONS_TO_INTEGER (Fcar (fdpid
), int, fd
);
120 /* for MSDOS fdpid is really (fd . tempfile) */
122 /* FD is -1 and FILE is "" when we didn't actually create a
123 temporary file in call-process. */
126 if (!(strcmp (SDATA (file
), NULL_DEVICE
) == 0 || SREF (file
, 0) == '\0'))
127 unlink (SDATA (file
));
128 #else /* not MSDOS */
129 CONS_TO_INTEGER (Fcdr (fdpid
), pid_t
, pid
);
131 if (call_process_exited
)
137 if (EMACS_KILLPG (pid
, SIGINT
) == 0)
139 ptrdiff_t count
= SPECPDL_INDEX ();
140 record_unwind_protect (call_process_kill
, fdpid
);
141 message1 ("Waiting for process to die...(type C-g again to kill it instantly)");
144 wait_for_termination (pid
);
146 specpdl_ptr
= specpdl
+ count
; /* Discard the unwind protect. */
147 message1 ("Waiting for process to die...done");
149 synch_process_alive
= 0;
151 #endif /* not MSDOS */
155 DEFUN ("call-process", Fcall_process
, Scall_process
, 1, MANY
, 0,
156 doc
: /* Call PROGRAM synchronously in separate process.
157 The remaining arguments are optional.
158 The program's input comes from file INFILE (nil means `/dev/null').
159 Insert output in BUFFER before point; t means current buffer; nil for BUFFER
160 means discard it; 0 means discard and don't wait; and `(:file FILE)', where
161 FILE is a file name string, means that it should be written to that file
162 \(if the file already exists it is overwritten).
163 BUFFER can also have the form (REAL-BUFFER STDERR-FILE); in that case,
164 REAL-BUFFER says what to do with standard output, as above,
165 while STDERR-FILE says what to do with standard error in the child.
166 STDERR-FILE may be nil (discard standard error output),
167 t (mix it with ordinary output), or a file name string.
169 Fourth arg DISPLAY non-nil means redisplay buffer as output is inserted.
170 Remaining arguments are strings passed as command arguments to PROGRAM.
172 If executable PROGRAM can't be found as an executable, `call-process'
173 signals a Lisp error. `call-process' reports errors in execution of
174 the program only through its return and output.
176 If BUFFER is 0, `call-process' returns immediately with value nil.
177 Otherwise it waits for PROGRAM to terminate
178 and returns a numeric exit status or a signal description string.
179 If you quit, the process is killed with SIGINT, or SIGKILL if you quit again.
181 usage: (call-process PROGRAM &optional INFILE BUFFER DISPLAY &rest ARGS) */)
182 (ptrdiff_t nargs
, Lisp_Object
*args
)
184 Lisp_Object infile
, buffer
, current_dir
, path
, cleanup_info_tail
;
186 int fd0
, fd1
, filefd
;
187 ptrdiff_t count
= SPECPDL_INDEX ();
191 /* File to use for stderr in the child.
192 t means use same as standard output. */
193 Lisp_Object error_file
;
194 Lisp_Object output_file
= Qnil
;
195 #ifdef MSDOS /* Demacs 1.1.1 91/10/16 HIRANO Satoshi */
196 char *outf
, *tempfile
= NULL
;
204 struct coding_system process_coding
; /* coding-system of process output */
205 struct coding_system argument_coding
; /* coding-system of arguments */
206 /* Set to the return value of Ffind_operation_coding_system. */
207 Lisp_Object coding_systems
;
208 bool output_to_buffer
= 1;
210 /* Qt denotes that Ffind_operation_coding_system is not yet called. */
213 CHECK_STRING (args
[0]);
218 /* Without asynchronous processes we cannot have BUFFER == 0. */
220 && (INTEGERP (CONSP (args
[2]) ? XCAR (args
[2]) : args
[2])))
221 error ("Operating system cannot handle asynchronous subprocesses");
222 #endif /* subprocesses */
224 /* Decide the coding-system for giving arguments. */
226 Lisp_Object val
, *args2
;
229 /* If arguments are supplied, we may have to encode them. */
232 bool must_encode
= 0;
233 Lisp_Object coding_attrs
;
235 for (i
= 4; i
< nargs
; i
++)
236 CHECK_STRING (args
[i
]);
238 for (i
= 4; i
< nargs
; i
++)
239 if (STRING_MULTIBYTE (args
[i
]))
242 if (!NILP (Vcoding_system_for_write
))
243 val
= Vcoding_system_for_write
;
244 else if (! must_encode
)
248 SAFE_NALLOCA (args2
, 1, nargs
+ 1);
249 args2
[0] = Qcall_process
;
250 for (i
= 0; i
< nargs
; i
++) args2
[i
+ 1] = args
[i
];
251 coding_systems
= Ffind_operation_coding_system (nargs
+ 1, args2
);
252 val
= CONSP (coding_systems
) ? XCDR (coding_systems
) : Qnil
;
254 val
= complement_process_encoding_system (val
);
255 setup_coding_system (Fcheck_coding_system (val
), &argument_coding
);
256 coding_attrs
= CODING_ID_ATTRS (argument_coding
.id
);
257 if (NILP (CODING_ATTR_ASCII_COMPAT (coding_attrs
)))
259 /* We should not use an ASCII incompatible coding system. */
260 val
= raw_text_coding_system (val
);
261 setup_coding_system (val
, &argument_coding
);
266 if (nargs
>= 2 && ! NILP (args
[1]))
268 infile
= Fexpand_file_name (args
[1], BVAR (current_buffer
, directory
));
269 CHECK_STRING (infile
);
272 infile
= build_string (NULL_DEVICE
);
278 /* If BUFFER is a list, its meaning is (BUFFER-FOR-STDOUT
279 FILE-FOR-STDERR), unless the first element is :file, in which case see
280 the next paragraph. */
282 && (! SYMBOLP (XCAR (buffer
))
283 || strcmp (SSDATA (SYMBOL_NAME (XCAR (buffer
))), ":file")))
285 if (CONSP (XCDR (buffer
)))
287 Lisp_Object stderr_file
;
288 stderr_file
= XCAR (XCDR (buffer
));
290 if (NILP (stderr_file
) || EQ (Qt
, stderr_file
))
291 error_file
= stderr_file
;
293 error_file
= Fexpand_file_name (stderr_file
, Qnil
);
296 buffer
= XCAR (buffer
);
299 /* If the buffer is (still) a list, it might be a (:file "file") spec. */
301 && SYMBOLP (XCAR (buffer
))
302 && ! strcmp (SSDATA (SYMBOL_NAME (XCAR (buffer
))), ":file"))
304 output_file
= Fexpand_file_name (XCAR (XCDR (buffer
)),
305 BVAR (current_buffer
, directory
));
306 CHECK_STRING (output_file
);
310 if (!(EQ (buffer
, Qnil
)
312 || INTEGERP (buffer
)))
314 Lisp_Object spec_buffer
;
315 spec_buffer
= buffer
;
316 buffer
= Fget_buffer_create (buffer
);
317 /* Mention the buffer name for a better error message. */
319 CHECK_BUFFER (spec_buffer
);
320 CHECK_BUFFER (buffer
);
326 /* Make sure that the child will be able to chdir to the current
327 buffer's current directory, or its unhandled equivalent. We
328 can't just have the child check for an error when it does the
329 chdir, since it's in a vfork.
331 We have to GCPRO around this because Fexpand_file_name,
332 Funhandled_file_name_directory, and Ffile_accessible_directory_p
333 might call a file name handling function. The argument list is
334 protected by the caller, so all we really have to worry about is
337 struct gcpro gcpro1
, gcpro2
, gcpro3
, gcpro4
, gcpro5
;
339 current_dir
= BVAR (current_buffer
, directory
);
341 GCPRO5 (infile
, buffer
, current_dir
, error_file
, output_file
);
343 current_dir
= Funhandled_file_name_directory (current_dir
);
344 if (NILP (current_dir
))
345 /* If the file name handler says that current_dir is unreachable, use
346 a sensible default. */
347 current_dir
= build_string ("~/");
348 current_dir
= expand_and_dir_to_file (current_dir
, Qnil
);
349 current_dir
= Ffile_name_as_directory (current_dir
);
351 if (NILP (Ffile_accessible_directory_p (current_dir
)))
352 report_file_error ("Setting current directory",
353 Fcons (BVAR (current_buffer
, directory
), Qnil
));
355 if (STRING_MULTIBYTE (infile
))
356 infile
= ENCODE_FILE (infile
);
357 if (STRING_MULTIBYTE (current_dir
))
358 current_dir
= ENCODE_FILE (current_dir
);
359 if (STRINGP (error_file
) && STRING_MULTIBYTE (error_file
))
360 error_file
= ENCODE_FILE (error_file
);
361 if (STRINGP (output_file
) && STRING_MULTIBYTE (output_file
))
362 output_file
= ENCODE_FILE (output_file
);
366 display_p
= INTERACTIVE
&& nargs
>= 4 && !NILP (args
[3]);
368 filefd
= emacs_open (SSDATA (infile
), O_RDONLY
, 0);
371 infile
= DECODE_FILE (infile
);
372 report_file_error ("Opening process input file", Fcons (infile
, Qnil
));
375 if (STRINGP (output_file
))
378 fd_output
= emacs_open (SSDATA (output_file
),
379 O_WRONLY
| O_TRUNC
| O_CREAT
| O_TEXT
,
381 #else /* not DOS_NT */
382 fd_output
= creat (SSDATA (output_file
), 0666);
383 #endif /* not DOS_NT */
386 output_file
= DECODE_FILE (output_file
);
387 report_file_error ("Opening process output file",
388 Fcons (output_file
, Qnil
));
390 if (STRINGP (error_file
) || NILP (error_file
))
391 output_to_buffer
= 0;
394 /* Search for program; barf if not found. */
396 struct gcpro gcpro1
, gcpro2
, gcpro3
, gcpro4
;
398 GCPRO4 (infile
, buffer
, current_dir
, error_file
);
399 openp (Vexec_path
, args
[0], Vexec_suffixes
, &path
, make_number (X_OK
));
404 emacs_close (filefd
);
405 report_file_error ("Searching for program", Fcons (args
[0], Qnil
));
408 /* If program file name starts with /: for quoting a magic name,
410 if (SBYTES (path
) > 2 && SREF (path
, 0) == '/'
411 && SREF (path
, 1) == ':')
412 path
= Fsubstring (path
, make_number (2), Qnil
);
414 new_argv
= SAFE_ALLOCA ((nargs
> 4 ? nargs
- 2 : 2) * sizeof *new_argv
);
418 struct gcpro gcpro1
, gcpro2
, gcpro3
, gcpro4
, gcpro5
;
420 GCPRO5 (infile
, buffer
, current_dir
, path
, error_file
);
421 argument_coding
.dst_multibyte
= 0;
422 for (i
= 4; i
< nargs
; i
++)
424 argument_coding
.src_multibyte
= STRING_MULTIBYTE (args
[i
]);
425 if (CODING_REQUIRE_ENCODING (&argument_coding
))
426 /* We must encode this argument. */
427 args
[i
] = encode_coding_string (&argument_coding
, args
[i
], 1);
430 for (i
= 4; i
< nargs
; i
++)
431 new_argv
[i
- 3] = SSDATA (args
[i
]);
436 new_argv
[0] = SSDATA (path
);
438 #ifdef MSDOS /* MW, July 1993 */
440 /* If we're redirecting STDOUT to a file, that file is already open
444 if ((outf
= egetenv ("TMPDIR")))
445 strcpy (tempfile
= alloca (strlen (outf
) + 20), outf
);
448 tempfile
= alloca (20);
451 dostounix_filename (tempfile
);
452 if (*tempfile
== '\0' || tempfile
[strlen (tempfile
) - 1] != '/')
453 strcat (tempfile
, "/");
454 strcat (tempfile
, "detmp.XXX");
456 outfilefd
= creat (tempfile
, S_IREAD
| S_IWRITE
);
458 emacs_close (filefd
);
459 report_file_error ("Opening process output file",
460 Fcons (build_string (tempfile
), Qnil
));
464 outfilefd
= fd_output
;
469 if (INTEGERP (buffer
))
472 fd1
= emacs_open (NULL_DEVICE
, O_WRONLY
, 0);
480 int pipe_errno
= errno
;
481 emacs_close (filefd
);
483 report_file_error ("Creating process pipe", Qnil
);
491 /* child_setup must clobber environ in systems with true vfork.
492 Protect it from permanent change. */
493 char **save_environ
= environ
;
499 /* Record that we're about to create a synchronous process. */
500 synch_process_alive
= 1;
502 /* These vars record information from process termination.
503 Clear them now before process can possibly terminate,
504 to avoid timing error if process terminates soon. */
505 synch_process_death
= 0;
506 synch_process_retcode
= 0;
507 synch_process_termsig
= 0;
509 if (NILP (error_file
))
510 fd_error
= emacs_open (NULL_DEVICE
, O_WRONLY
, 0);
511 else if (STRINGP (error_file
))
514 fd_error
= emacs_open (SSDATA (error_file
),
515 O_WRONLY
| O_TRUNC
| O_CREAT
| O_TEXT
,
517 #else /* not DOS_NT */
518 fd_error
= creat (SSDATA (error_file
), 0666);
519 #endif /* not DOS_NT */
524 emacs_close (filefd
);
532 if (NILP (error_file
))
533 error_file
= build_string (NULL_DEVICE
);
534 else if (STRINGP (error_file
))
535 error_file
= DECODE_FILE (error_file
);
536 report_file_error ("Cannot redirect stderr", Fcons (error_file
, Qnil
));
539 #ifdef MSDOS /* MW, July 1993 */
540 /* Note that on MSDOS `child_setup' actually returns the child process
541 exit status, not its PID, so we assign it to `synch_process_retcode'
543 pid
= child_setup (filefd
, outfilefd
, fd_error
, new_argv
, 0, current_dir
);
545 /* Record that the synchronous process exited and note its
546 termination status. */
547 synch_process_alive
= 0;
548 synch_process_retcode
= pid
;
549 if (synch_process_retcode
< 0) /* means it couldn't be exec'ed */
551 synchronize_system_messages_locale ();
552 synch_process_death
= strerror (errno
);
555 emacs_close (outfilefd
);
556 if (fd_error
!= outfilefd
)
557 emacs_close (fd_error
);
558 fd1
= -1; /* No harm in closing that one! */
561 /* Since CRLF is converted to LF within `decode_coding', we
562 can always open a file with binary mode. */
563 fd0
= emacs_open (tempfile
, O_RDONLY
| O_BINARY
, 0);
567 emacs_close (filefd
);
568 report_file_error ("Cannot re-open temporary file",
569 Fcons (build_string (tempfile
), Qnil
));
573 fd0
= -1; /* We are not going to read from tempfile. */
574 #else /* not MSDOS */
576 pid
= child_setup (filefd
, fd1
, fd_error
, new_argv
, 0, current_dir
);
577 #else /* not WINDOWSNT */
581 /* vfork, and prevent local vars from being clobbered by the vfork. */
583 Lisp_Object
volatile buffer_volatile
= buffer
;
584 Lisp_Object
volatile coding_systems_volatile
= coding_systems
;
585 Lisp_Object
volatile current_dir_volatile
= current_dir
;
586 bool volatile display_p_volatile
= display_p
;
587 bool volatile output_to_buffer_volatile
= output_to_buffer
;
588 bool volatile sa_must_free_volatile
= sa_must_free
;
589 int volatile fd0_volatile
= fd0
;
590 int volatile fd1_volatile
= fd1
;
591 int volatile fd_error_volatile
= fd_error
;
592 int volatile fd_output_volatile
= fd_output
;
593 int volatile filefd_volatile
= filefd
;
594 ptrdiff_t volatile count_volatile
= count
;
595 ptrdiff_t volatile sa_count_volatile
= sa_count
;
596 char **volatile new_argv_volatile
= new_argv
;
597 char **volatile new_save_environ
= save_environ
;
601 buffer
= buffer_volatile
;
602 coding_systems
= coding_systems_volatile
;
603 current_dir
= current_dir_volatile
;
604 display_p
= display_p_volatile
;
605 output_to_buffer
= output_to_buffer_volatile
;
606 sa_must_free
= sa_must_free_volatile
;
609 fd_error
= fd_error_volatile
;
610 fd_output
= fd_output_volatile
;
611 filefd
= filefd_volatile
;
612 count
= count_volatile
;
613 sa_count
= sa_count_volatile
;
614 new_argv
= new_argv_volatile
;
615 save_environ
= new_save_environ
;
625 /* Emacs ignores SIGPIPE, but the child should not. */
626 signal (SIGPIPE
, SIG_DFL
);
628 child_setup (filefd
, fd1
, fd_error
, new_argv
, 0, current_dir
);
634 #endif /* not WINDOWSNT */
636 /* The MSDOS case did this already. */
638 emacs_close (fd_error
);
639 #endif /* not MSDOS */
641 environ
= save_environ
;
643 /* Close most of our file descriptors, but not fd0
644 since we will use that to read input from. */
645 emacs_close (filefd
);
647 emacs_close (fd_output
);
648 if (fd1
>= 0 && fd1
!= fd_error
)
657 report_file_error ("Doing vfork", Qnil
);
660 if (INTEGERP (buffer
))
667 /* Enable sending signal if user quits below. */
668 call_process_exited
= 0;
671 /* MSDOS needs different cleanup information. */
672 cleanup_info_tail
= build_string (tempfile
? tempfile
: "");
674 cleanup_info_tail
= INTEGER_TO_CONS (pid
);
675 #endif /* not MSDOS */
676 record_unwind_protect (call_process_cleanup
,
677 Fcons (Fcurrent_buffer (),
678 Fcons (INTEGER_TO_CONS (fd0
),
679 cleanup_info_tail
)));
681 if (BUFFERP (buffer
))
682 Fset_buffer (buffer
);
686 /* If BUFFER is nil, we must read process output once and then
687 discard it, so setup coding system but with nil. */
688 setup_coding_system (Qnil
, &process_coding
);
689 process_coding
.dst_multibyte
= 0;
693 Lisp_Object val
, *args2
;
696 if (!NILP (Vcoding_system_for_read
))
697 val
= Vcoding_system_for_read
;
700 if (EQ (coding_systems
, Qt
))
704 SAFE_NALLOCA (args2
, 1, nargs
+ 1);
705 args2
[0] = Qcall_process
;
706 for (i
= 0; i
< nargs
; i
++) args2
[i
+ 1] = args
[i
];
708 = Ffind_operation_coding_system (nargs
+ 1, args2
);
710 if (CONSP (coding_systems
))
711 val
= XCAR (coding_systems
);
712 else if (CONSP (Vdefault_process_coding_system
))
713 val
= XCAR (Vdefault_process_coding_system
);
717 Fcheck_coding_system (val
);
718 /* In unibyte mode, character code conversion should not take
719 place but EOL conversion should. So, setup raw-text or one
720 of the subsidiary according to the information just setup. */
721 if (NILP (BVAR (current_buffer
, enable_multibyte_characters
))
723 val
= raw_text_coding_system (val
);
724 setup_coding_system (val
, &process_coding
);
725 process_coding
.dst_multibyte
726 = ! NILP (BVAR (current_buffer
, enable_multibyte_characters
));
728 process_coding
.src_multibyte
= 0;
733 if (output_to_buffer
)
735 enum { CALLPROC_BUFFER_SIZE_MIN
= 16 * 1024 };
736 enum { CALLPROC_BUFFER_SIZE_MAX
= 4 * CALLPROC_BUFFER_SIZE_MIN
};
737 char buf
[CALLPROC_BUFFER_SIZE_MAX
];
738 int bufsize
= CALLPROC_BUFFER_SIZE_MIN
;
741 EMACS_INT total_read
= 0;
743 bool display_on_the_fly
= display_p
;
744 struct coding_system saved_coding
;
746 saved_coding
= process_coding
;
749 /* Repeatedly read until we've filled as much as possible
750 of the buffer size we have. But don't read
751 less than 1024--save that for the next bufferful. */
753 while (nread
< bufsize
- 1024)
755 int this_read
= emacs_read (fd0
, buf
+ nread
,
763 process_coding
.mode
|= CODING_MODE_LAST_BLOCK
;
768 total_read
+= this_read
;
770 if (display_on_the_fly
)
774 /* Now NREAD is the total amount of data in the buffer. */
779 if (NILP (BVAR (current_buffer
, enable_multibyte_characters
))
780 && ! CODING_MAY_REQUIRE_DECODING (&process_coding
))
781 insert_1_both (buf
, nread
, nread
, 0, 1, 0);
783 { /* We have to decode the input. */
785 ptrdiff_t count1
= SPECPDL_INDEX ();
787 XSETBUFFER (curbuf
, current_buffer
);
788 /* We cannot allow after-change-functions be run
789 during decoding, because that might modify the
790 buffer, while we rely on process_coding.produced to
791 faithfully reflect inserted text until we
792 TEMP_SET_PT_BOTH below. */
793 specbind (Qinhibit_modification_hooks
, Qt
);
794 decode_coding_c_string (&process_coding
,
795 (unsigned char *) buf
, nread
, curbuf
);
796 unbind_to (count1
, Qnil
);
797 if (display_on_the_fly
798 && CODING_REQUIRE_DETECTION (&saved_coding
)
799 && ! CODING_REQUIRE_DETECTION (&process_coding
))
801 /* We have detected some coding system. But,
802 there's a possibility that the detection was
803 done by insufficient data. So, we give up
804 displaying on the fly. */
805 if (process_coding
.produced
> 0)
806 del_range_2 (process_coding
.dst_pos
,
807 process_coding
.dst_pos_byte
,
808 process_coding
.dst_pos
809 + process_coding
.produced_char
,
810 process_coding
.dst_pos_byte
811 + process_coding
.produced
, 0);
812 display_on_the_fly
= 0;
813 process_coding
= saved_coding
;
815 /* This is to make the above condition always
816 fails in the future. */
817 saved_coding
.common_flags
818 &= ~CODING_REQUIRE_DETECTION_MASK
;
822 TEMP_SET_PT_BOTH (PT
+ process_coding
.produced_char
,
823 PT_BYTE
+ process_coding
.produced
);
824 carryover
= process_coding
.carryover_bytes
;
826 memcpy (buf
, process_coding
.carryover
,
827 process_coding
.carryover_bytes
);
831 if (process_coding
.mode
& CODING_MODE_LAST_BLOCK
)
834 /* Make the buffer bigger as we continue to read more data,
835 but not past CALLPROC_BUFFER_SIZE_MAX. */
836 if (bufsize
< CALLPROC_BUFFER_SIZE_MAX
&& total_read
> 32 * bufsize
)
837 if ((bufsize
*= 2) > CALLPROC_BUFFER_SIZE_MAX
)
838 bufsize
= CALLPROC_BUFFER_SIZE_MAX
;
843 prepare_menu_bars ();
845 redisplay_preserve_echo_area (1);
846 /* This variable might have been set to 0 for code
847 detection. In that case, we set it back to 1 because
848 we should have already detected a coding system. */
849 display_on_the_fly
= 1;
856 Vlast_coding_system_used
= CODING_ID_NAME (process_coding
.id
);
857 /* If the caller required, let the buffer inherit the
858 coding-system used to decode the process output. */
859 if (inherit_process_coding_system
)
860 call1 (intern ("after-insert-file-set-buffer-file-coding-system"),
861 make_number (total_read
));
865 /* Wait for it to terminate, unless it already has. */
866 if (output_to_buffer
)
867 wait_for_termination (pid
);
869 interruptible_wait_for_termination (pid
);
874 /* Don't kill any children that the subprocess may have left behind
876 call_process_exited
= 1;
879 unbind_to (count
, Qnil
);
881 if (synch_process_termsig
)
885 synchronize_system_messages_locale ();
886 signame
= strsignal (synch_process_termsig
);
891 synch_process_death
= signame
;
894 if (synch_process_death
)
895 return code_convert_string_norecord (build_string (synch_process_death
),
896 Vlocale_coding_system
, 0);
897 return make_number (synch_process_retcode
);
901 delete_temp_file (Lisp_Object name
)
903 /* Suppress jka-compr handling, etc. */
904 ptrdiff_t count
= SPECPDL_INDEX ();
905 specbind (intern ("file-name-handler-alist"), Qnil
);
906 internal_delete_file (name
);
907 unbind_to (count
, Qnil
);
911 DEFUN ("call-process-region", Fcall_process_region
, Scall_process_region
,
913 doc
: /* Send text from START to END to a synchronous process running PROGRAM.
914 The remaining arguments are optional.
915 Delete the text if fourth arg DELETE is non-nil.
917 Insert output in BUFFER before point; t means current buffer; nil for
918 BUFFER means discard it; 0 means discard and don't wait; and `(:file
919 FILE)', where FILE is a file name string, means that it should be
920 written to that file (if the file already exists it is overwritten).
921 BUFFER can also have the form (REAL-BUFFER STDERR-FILE); in that case,
922 REAL-BUFFER says what to do with standard output, as above,
923 while STDERR-FILE says what to do with standard error in the child.
924 STDERR-FILE may be nil (discard standard error output),
925 t (mix it with ordinary output), or a file name string.
927 Sixth arg DISPLAY non-nil means redisplay buffer as output is inserted.
928 Remaining args are passed to PROGRAM at startup as command args.
930 If BUFFER is 0, `call-process-region' returns immediately with value nil.
931 Otherwise it waits for PROGRAM to terminate
932 and returns a numeric exit status or a signal description string.
933 If you quit, the process is killed with SIGINT, or SIGKILL if you quit again.
935 usage: (call-process-region START END PROGRAM &optional DELETE BUFFER DISPLAY &rest ARGS) */)
936 (ptrdiff_t nargs
, Lisp_Object
*args
)
939 Lisp_Object filename_string
;
940 register Lisp_Object start
, end
;
941 ptrdiff_t count
= SPECPDL_INDEX ();
942 /* Qt denotes we have not yet called Ffind_operation_coding_system. */
943 Lisp_Object coding_systems
;
944 Lisp_Object val
, *args2
;
948 if (STRINGP (Vtemporary_file_directory
))
949 tmpdir
= Vtemporary_file_directory
;
953 if (getenv ("TMPDIR"))
954 tmpdir
= build_string (getenv ("TMPDIR"));
956 tmpdir
= build_string ("/tmp/");
959 if ((outf
= egetenv ("TMPDIR"))
960 || (outf
= egetenv ("TMP"))
961 || (outf
= egetenv ("TEMP")))
962 tmpdir
= build_string (outf
);
964 tmpdir
= Ffile_name_as_directory (build_string ("c:/temp"));
970 Lisp_Object pattern
= Fexpand_file_name (Vtemp_file_name_pattern
, tmpdir
);
971 char *tempfile
= SAFE_ALLOCA (SBYTES (pattern
) + 1);
972 memcpy (tempfile
, SDATA (pattern
), SBYTES (pattern
) + 1);
980 fd
= mkstemp (tempfile
);
983 report_file_error ("Failed to open temporary file",
984 Fcons (build_string (tempfile
), Qnil
));
992 filename_string
= build_string (tempfile
);
993 GCPRO1 (filename_string
);
999 /* Decide coding-system of the contents of the temporary file. */
1000 if (!NILP (Vcoding_system_for_write
))
1001 val
= Vcoding_system_for_write
;
1002 else if (NILP (BVAR (current_buffer
, enable_multibyte_characters
)))
1007 SAFE_NALLOCA (args2
, 1, nargs
+ 1);
1008 args2
[0] = Qcall_process_region
;
1009 for (i
= 0; i
< nargs
; i
++) args2
[i
+ 1] = args
[i
];
1010 coding_systems
= Ffind_operation_coding_system (nargs
+ 1, args2
);
1011 val
= CONSP (coding_systems
) ? XCDR (coding_systems
) : Qnil
;
1014 val
= complement_process_encoding_system (val
);
1017 ptrdiff_t count1
= SPECPDL_INDEX ();
1019 specbind (intern ("coding-system-for-write"), val
);
1020 /* POSIX lets mk[s]temp use "."; don't invoke jka-compr if we
1021 happen to get a ".Z" suffix. */
1022 specbind (intern ("file-name-handler-alist"), Qnil
);
1023 Fwrite_region (start
, end
, filename_string
, Qnil
, Qlambda
, Qnil
, Qnil
);
1025 unbind_to (count1
, Qnil
);
1028 /* Note that Fcall_process takes care of binding
1029 coding-system-for-read. */
1031 record_unwind_protect (delete_temp_file
, filename_string
);
1033 if (nargs
> 3 && !NILP (args
[3]))
1034 Fdelete_region (start
, end
);
1046 args
[1] = filename_string
;
1048 RETURN_UNGCPRO (unbind_to (count
, Fcall_process (nargs
, args
)));
1052 static int relocate_fd (int fd
, int minfd
);
1056 add_env (char **env
, char **new_env
, char *string
)
1063 /* See if this string duplicates any string already in the env.
1064 If so, don't put it in.
1065 When an env var has multiple definitions,
1066 we keep the definition that comes first in process-environment. */
1067 for (ep
= env
; ok
&& ep
!= new_env
; ep
++)
1069 char *p
= *ep
, *q
= string
;
1075 /* The string is a lone variable name; keep it for now, we
1076 will remove it later. It is a placeholder for a
1077 variable that is not to be included in the environment. */
1085 *new_env
++ = string
;
1089 /* This is the last thing run in a newly forked inferior
1090 either synchronous or asynchronous.
1091 Copy descriptors IN, OUT and ERR as descriptors 0, 1 and 2.
1092 Initialize inferior's priority, pgrp, connected dir and environment.
1093 then exec another program based on new_argv.
1095 This function may change environ for the superior process.
1096 Therefore, the superior process must save and restore the value
1097 of environ around the vfork and the call to this function.
1099 If SET_PGRP, put the subprocess into a separate process group.
1101 CURRENT_DIR is an elisp string giving the path of the current
1102 directory the subprocess should have. Since we can't really signal
1103 a decent error from within the child, this should be verified as an
1104 executable directory by the parent. */
1107 child_setup (int in
, int out
, int err
, char **new_argv
, bool set_pgrp
,
1108 Lisp_Object current_dir
)
1115 #endif /* WINDOWSNT */
1117 pid_t pid
= getpid ();
1119 /* Close Emacs's descriptors that this process should not have. */
1120 close_process_descs ();
1122 /* DOS_NT isn't in a vfork, so if we are in the middle of load-file,
1123 we will lose if we call close_load_descs here. */
1125 close_load_descs ();
1128 /* Note that use of alloca is always safe here. It's obvious for systems
1129 that do not have true vfork or that have true (stack) alloca.
1130 If using vfork and C_ALLOCA (when Emacs used to include
1131 src/alloca.c) it is safe because that changes the superior's
1132 static variables as if the superior had done alloca and will be
1133 cleaned up in the usual way. */
1135 register char *temp
;
1136 size_t i
; /* size_t, because ptrdiff_t might overflow here! */
1138 i
= SBYTES (current_dir
);
1140 /* MSDOS must have all environment variables malloc'ed, because
1141 low-level libc functions that launch subsidiary processes rely
1143 pwd_var
= xmalloc (i
+ 6);
1145 pwd_var
= alloca (i
+ 6);
1148 memcpy (pwd_var
, "PWD=", 4);
1149 memcpy (temp
, SDATA (current_dir
), i
);
1150 if (!IS_DIRECTORY_SEP (temp
[i
- 1])) temp
[i
++] = DIRECTORY_SEP
;
1154 /* We can't signal an Elisp error here; we're in a vfork. Since
1155 the callers check the current directory before forking, this
1156 should only return an error if the directory's permissions
1157 are changed between the check and this chdir, but we should
1159 if (chdir (temp
) < 0)
1162 /* Get past the drive letter, so that d:/ is left alone. */
1163 if (i
> 2 && IS_DEVICE_SEP (temp
[1]) && IS_DIRECTORY_SEP (temp
[2]))
1170 /* Strip trailing slashes for PWD, but leave "/" and "//" alone. */
1171 while (i
> 2 && IS_DIRECTORY_SEP (temp
[i
- 1]))
1175 /* Set `env' to a vector of the strings in the environment. */
1177 register Lisp_Object tem
;
1178 register char **new_env
;
1180 register int new_length
;
1181 Lisp_Object display
= Qnil
;
1185 for (tem
= Vprocess_environment
;
1186 CONSP (tem
) && STRINGP (XCAR (tem
));
1189 if (strncmp (SSDATA (XCAR (tem
)), "DISPLAY", 7) == 0
1190 && (SDATA (XCAR (tem
)) [7] == '\0'
1191 || SDATA (XCAR (tem
)) [7] == '='))
1192 /* DISPLAY is specified in process-environment. */
1197 /* If not provided yet, use the frame's DISPLAY. */
1200 Lisp_Object tmp
= Fframe_parameter (selected_frame
, Qdisplay
);
1201 if (!STRINGP (tmp
) && CONSP (Vinitial_environment
))
1202 /* If still not found, Look for DISPLAY in Vinitial_environment. */
1203 tmp
= Fgetenv_internal (build_string ("DISPLAY"),
1204 Vinitial_environment
);
1212 /* new_length + 2 to include PWD and terminating 0. */
1213 env
= new_env
= alloca ((new_length
+ 2) * sizeof *env
);
1214 /* If we have a PWD envvar, pass one down,
1215 but with corrected value. */
1216 if (egetenv ("PWD"))
1217 *new_env
++ = pwd_var
;
1219 if (STRINGP (display
))
1221 char *vdata
= alloca (sizeof "DISPLAY=" + SBYTES (display
));
1222 strcpy (vdata
, "DISPLAY=");
1223 strcat (vdata
, SSDATA (display
));
1224 new_env
= add_env (env
, new_env
, vdata
);
1228 for (tem
= Vprocess_environment
;
1229 CONSP (tem
) && STRINGP (XCAR (tem
));
1231 new_env
= add_env (env
, new_env
, SSDATA (XCAR (tem
)));
1235 /* Remove variable names without values. */
1239 while (*q
!= 0 && strchr (*q
, '=') == NULL
)
1249 prepare_standard_handles (in
, out
, err
, handles
);
1250 set_process_dir (SDATA (current_dir
));
1251 /* Spawn the child. (See ntproc.c:Spawnve). */
1252 cpid
= spawnve (_P_NOWAIT
, new_argv
[0], new_argv
, env
);
1253 reset_standard_handles (in
, out
, err
, handles
);
1255 /* An error occurred while trying to spawn the process. */
1256 report_file_error ("Spawning child process", Qnil
);
1259 #else /* not WINDOWSNT */
1260 /* Make sure that in, out, and err are not actually already in
1261 descriptors zero, one, or two; this could happen if Emacs is
1262 started with its standard in, out, or error closed, as might
1265 int oin
= in
, oout
= out
;
1267 /* We have to avoid relocating the same descriptor twice! */
1269 in
= relocate_fd (in
, 3);
1274 out
= relocate_fd (out
, 3);
1278 else if (err
== oout
)
1281 err
= relocate_fd (err
, 3);
1295 if (err
!= in
&& err
!= out
)
1301 /* execvp does not accept an environment arg so the only way
1302 to pass this environment is to set environ. Our caller
1303 is responsible for restoring the ambient value of environ. */
1305 execvp (new_argv
[0], new_argv
);
1307 emacs_write (1, "Can't exec program: ", 20);
1308 emacs_write (1, new_argv
[0], strlen (new_argv
[0]));
1309 emacs_write (1, "\n", 1);
1313 pid
= run_msdos_command (new_argv
, pwd_var
+ 4, in
, out
, err
, env
);
1316 /* An error occurred while trying to run the subprocess. */
1317 report_file_error ("Spawning child process", Qnil
);
1320 #endif /* not WINDOWSNT */
1324 /* Move the file descriptor FD so that its number is not less than MINFD.
1325 If the file descriptor is moved at all, the original is freed. */
1327 relocate_fd (int fd
, int minfd
)
1333 int new = fcntl (fd
, F_DUPFD
, minfd
);
1336 const char *message_1
= "Error while setting up child: ";
1337 const char *errmessage
= strerror (errno
);
1338 const char *message_2
= "\n";
1339 emacs_write (2, message_1
, strlen (message_1
));
1340 emacs_write (2, errmessage
, strlen (errmessage
));
1341 emacs_write (2, message_2
, strlen (message_2
));
1348 #endif /* not WINDOWSNT */
1351 getenv_internal_1 (const char *var
, ptrdiff_t varlen
, char **value
,
1352 ptrdiff_t *valuelen
, Lisp_Object env
)
1354 for (; CONSP (env
); env
= XCDR (env
))
1356 Lisp_Object entry
= XCAR (env
);
1358 && SBYTES (entry
) >= varlen
1360 /* NT environment variables are case insensitive. */
1361 && ! strnicmp (SDATA (entry
), var
, varlen
)
1362 #else /* not WINDOWSNT */
1363 && ! memcmp (SDATA (entry
), var
, varlen
)
1364 #endif /* not WINDOWSNT */
1367 if (SBYTES (entry
) > varlen
&& SREF (entry
, varlen
) == '=')
1369 *value
= SSDATA (entry
) + (varlen
+ 1);
1370 *valuelen
= SBYTES (entry
) - (varlen
+ 1);
1373 else if (SBYTES (entry
) == varlen
)
1375 /* Lone variable names in Vprocess_environment mean that
1376 variable should be removed from the environment. */
1386 getenv_internal (const char *var
, ptrdiff_t varlen
, char **value
,
1387 ptrdiff_t *valuelen
, Lisp_Object frame
)
1389 /* Try to find VAR in Vprocess_environment first. */
1390 if (getenv_internal_1 (var
, varlen
, value
, valuelen
,
1391 Vprocess_environment
))
1392 return *value
? 1 : 0;
1394 /* For DISPLAY try to get the values from the frame or the initial env. */
1395 if (strcmp (var
, "DISPLAY") == 0)
1398 = Fframe_parameter (NILP (frame
) ? selected_frame
: frame
, Qdisplay
);
1399 if (STRINGP (display
))
1401 *value
= SSDATA (display
);
1402 *valuelen
= SBYTES (display
);
1405 /* If still not found, Look for DISPLAY in Vinitial_environment. */
1406 if (getenv_internal_1 (var
, varlen
, value
, valuelen
,
1407 Vinitial_environment
))
1408 return *value
? 1 : 0;
1414 DEFUN ("getenv-internal", Fgetenv_internal
, Sgetenv_internal
, 1, 2, 0,
1415 doc
: /* Get the value of environment variable VARIABLE.
1416 VARIABLE should be a string. Value is nil if VARIABLE is undefined in
1417 the environment. Otherwise, value is a string.
1419 This function searches `process-environment' for VARIABLE.
1421 If optional parameter ENV is a list, then search this list instead of
1422 `process-environment', and return t when encountering a negative entry
1423 \(an entry for a variable with no value). */)
1424 (Lisp_Object variable
, Lisp_Object env
)
1429 CHECK_STRING (variable
);
1432 if (getenv_internal_1 (SSDATA (variable
), SBYTES (variable
),
1433 &value
, &valuelen
, env
))
1434 return value
? make_string (value
, valuelen
) : Qt
;
1438 else if (getenv_internal (SSDATA (variable
), SBYTES (variable
),
1439 &value
, &valuelen
, env
))
1440 return make_string (value
, valuelen
);
1445 /* A version of getenv that consults the Lisp environment lists,
1446 easily callable from C. */
1448 egetenv (const char *var
)
1453 if (getenv_internal (var
, strlen (var
), &value
, &valuelen
, Qnil
))
1460 /* This is run before init_cmdargs. */
1463 init_callproc_1 (void)
1466 const char *etc_dir
= ns_etc_directory ();
1467 const char *path_exec
= ns_exec_path ();
1470 Vdata_directory
= decode_env_path ("EMACSDATA",
1475 Vdata_directory
= Ffile_name_as_directory (Fcar (Vdata_directory
));
1477 Vdoc_directory
= decode_env_path ("EMACSDOC",
1482 Vdoc_directory
= Ffile_name_as_directory (Fcar (Vdoc_directory
));
1484 /* Check the EMACSPATH environment variable, defaulting to the
1485 PATH_EXEC path from epaths.h. */
1486 Vexec_path
= decode_env_path ("EMACSPATH",
1488 path_exec
? path_exec
:
1491 Vexec_directory
= Ffile_name_as_directory (Fcar (Vexec_path
));
1492 /* FIXME? For ns, path_exec should go at the front? */
1493 Vexec_path
= nconc2 (decode_env_path ("PATH", ""), Vexec_path
);
1496 /* This is run after init_cmdargs, when Vinstallation_directory is valid. */
1499 init_callproc (void)
1501 char *data_dir
= egetenv ("EMACSDATA");
1504 Lisp_Object tempdir
;
1508 const char *etc_dir
= ns_etc_directory ();
1511 data_dir
= alloca (strlen (etc_dir
) + 1);
1512 strcpy (data_dir
, etc_dir
);
1517 if (!NILP (Vinstallation_directory
))
1519 /* Add to the path the lib-src subdir of the installation dir. */
1521 tem
= Fexpand_file_name (build_string ("lib-src"),
1522 Vinstallation_directory
);
1524 /* MSDOS uses wrapped binaries, so don't do this. */
1525 if (NILP (Fmember (tem
, Vexec_path
)))
1528 const char *path_exec
= ns_exec_path ();
1530 Vexec_path
= decode_env_path ("EMACSPATH",
1532 path_exec
? path_exec
:
1535 Vexec_path
= Fcons (tem
, Vexec_path
);
1536 Vexec_path
= nconc2 (decode_env_path ("PATH", ""), Vexec_path
);
1539 Vexec_directory
= Ffile_name_as_directory (tem
);
1540 #endif /* not MSDOS */
1542 /* Maybe use ../etc as well as ../lib-src. */
1545 tem
= Fexpand_file_name (build_string ("etc"),
1546 Vinstallation_directory
);
1547 Vdoc_directory
= Ffile_name_as_directory (tem
);
1551 /* Look for the files that should be in etc. We don't use
1552 Vinstallation_directory, because these files are never installed
1553 near the executable, and they are never in the build
1554 directory when that's different from the source directory.
1556 Instead, if these files are not in the nominal place, we try the
1557 source directory. */
1560 Lisp_Object tem
, tem1
, srcdir
;
1562 srcdir
= Fexpand_file_name (build_string ("../src/"),
1563 build_string (PATH_DUMPLOADSEARCH
));
1564 tem
= Fexpand_file_name (build_string ("GNU"), Vdata_directory
);
1565 tem1
= Ffile_exists_p (tem
);
1566 if (!NILP (Fequal (srcdir
, Vinvocation_directory
)) || NILP (tem1
))
1569 newdir
= Fexpand_file_name (build_string ("../etc/"),
1570 build_string (PATH_DUMPLOADSEARCH
));
1571 tem
= Fexpand_file_name (build_string ("GNU"), newdir
);
1572 tem1
= Ffile_exists_p (tem
);
1574 Vdata_directory
= newdir
;
1582 tempdir
= Fdirectory_file_name (Vexec_directory
);
1583 if (! file_accessible_directory_p (SSDATA (tempdir
)))
1584 dir_warning ("arch-dependent data dir", Vexec_directory
);
1587 tempdir
= Fdirectory_file_name (Vdata_directory
);
1588 if (! file_accessible_directory_p (SSDATA (tempdir
)))
1589 dir_warning ("arch-independent data dir", Vdata_directory
);
1591 sh
= (char *) getenv ("SHELL");
1592 Vshell_file_name
= build_string (sh
? sh
: "/bin/sh");
1595 Vshared_game_score_directory
= Qnil
;
1597 Vshared_game_score_directory
= build_string (PATH_GAME
);
1598 if (NILP (Ffile_accessible_directory_p (Vshared_game_score_directory
)))
1599 Vshared_game_score_directory
= Qnil
;
1604 set_initial_environment (void)
1607 for (envp
= environ
; *envp
; envp
++)
1608 Vprocess_environment
= Fcons (build_string (*envp
),
1609 Vprocess_environment
);
1610 /* Ideally, the `copy' shouldn't be necessary, but it seems it's frequent
1611 to use `delete' and friends on process-environment. */
1612 Vinitial_environment
= Fcopy_sequence (Vprocess_environment
);
1616 syms_of_callproc (void)
1619 Vtemp_file_name_pattern
= build_string ("emacsXXXXXX");
1620 #elif defined (WINDOWSNT)
1621 Vtemp_file_name_pattern
= build_string ("emXXXXXX");
1623 Vtemp_file_name_pattern
= build_string ("detmp.XXX");
1625 staticpro (&Vtemp_file_name_pattern
);
1627 DEFVAR_LISP ("shell-file-name", Vshell_file_name
,
1628 doc
: /* File name to load inferior shells from.
1629 Initialized from the SHELL environment variable, or to a system-dependent
1630 default if SHELL is not set. */);
1632 DEFVAR_LISP ("exec-path", Vexec_path
,
1633 doc
: /* List of directories to search programs to run in subprocesses.
1634 Each element is a string (directory name) or nil (try default directory). */);
1636 DEFVAR_LISP ("exec-suffixes", Vexec_suffixes
,
1637 doc
: /* List of suffixes to try to find executable file names.
1638 Each element is a string. */);
1639 Vexec_suffixes
= Qnil
;
1641 DEFVAR_LISP ("exec-directory", Vexec_directory
,
1642 doc
: /* Directory for executables for Emacs to invoke.
1643 More generally, this includes any architecture-dependent files
1644 that are built and installed from the Emacs distribution. */);
1646 DEFVAR_LISP ("data-directory", Vdata_directory
,
1647 doc
: /* Directory of machine-independent files that come with GNU Emacs.
1648 These are files intended for Emacs to use while it runs. */);
1650 DEFVAR_LISP ("doc-directory", Vdoc_directory
,
1651 doc
: /* Directory containing the DOC file that comes with GNU Emacs.
1652 This is usually the same as `data-directory'. */);
1654 DEFVAR_LISP ("configure-info-directory", Vconfigure_info_directory
,
1655 doc
: /* For internal use by the build procedure only.
1656 This is the name of the directory in which the build procedure installed
1657 Emacs's info files; the default value for `Info-default-directory-list'
1659 Vconfigure_info_directory
= build_string (PATH_INFO
);
1661 DEFVAR_LISP ("shared-game-score-directory", Vshared_game_score_directory
,
1662 doc
: /* Directory of score files for games which come with GNU Emacs.
1663 If this variable is nil, then Emacs is unable to use a shared directory. */);
1665 Vshared_game_score_directory
= Qnil
;
1667 Vshared_game_score_directory
= build_string (PATH_GAME
);
1670 DEFVAR_LISP ("initial-environment", Vinitial_environment
,
1671 doc
: /* List of environment variables inherited from the parent process.
1672 Each element should be a string of the form ENVVARNAME=VALUE.
1673 The elements must normally be decoded (using `locale-coding-system') for use. */);
1674 Vinitial_environment
= Qnil
;
1676 DEFVAR_LISP ("process-environment", Vprocess_environment
,
1677 doc
: /* List of overridden environment variables for subprocesses to inherit.
1678 Each element should be a string of the form ENVVARNAME=VALUE.
1680 Entries in this list take precedence to those in the frame-local
1681 environments. Therefore, let-binding `process-environment' is an easy
1682 way to temporarily change the value of an environment variable,
1683 irrespective of where it comes from. To use `process-environment' to
1684 remove an environment variable, include only its name in the list,
1687 This variable is set to nil when Emacs starts.
1689 If multiple entries define the same variable, the first one always
1692 Non-ASCII characters are encoded according to the initial value of
1693 `locale-coding-system', i.e. the elements must normally be decoded for
1696 See `setenv' and `getenv'. */);
1697 Vprocess_environment
= Qnil
;
1699 defsubr (&Scall_process
);
1700 defsubr (&Sgetenv_internal
);
1701 defsubr (&Scall_process_region
);