src/process.h

   1 /* Definitions for asynchronous process control in GNU Emacs.
   2    Copyright (C) 1985, 1994 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 /* This structure records information about a subprocess
  23    or network connection.
  24
  25    Every field in this structure except for the first two
  26    must be a Lisp_Object, for GC's sake.  */
  27
  28 struct Lisp_Process
  29   {
  30     EMACS_INT size;
  31     struct Lisp_Vector *v_next;
  32     /* Descriptor by which we read from this process */
  33     Lisp_Object infd;
  34     /* Descriptor by which we write to this process */
  35     Lisp_Object outfd;
  36     /* Descriptor for the tty which this process is using.
  37        nil if we didn't record it (on some systems, there's no need).  */
  38     Lisp_Object subtty;
  39     /* Name of subprocess terminal.  */
  40     Lisp_Object tty_name;
  41     /* Name of this process */
  42     Lisp_Object name;
  43     /* List of command arguments that this process was run with */
  44     Lisp_Object command;
  45     /* (funcall FILTER PROC STRING)  (if FILTER is non-nil)
  46        to dispose of a bunch of chars from the process all at once */
  47     Lisp_Object filter;
  48     /* (funcall SENTINEL PROCESS) when process state changes */
  49     Lisp_Object sentinel;
  50     /* Buffer that output is going to */
  51     Lisp_Object buffer;
  52     /* Number of this process */
  53     Lisp_Object pid;
  54     /* Non-nil if this is really a command channel */
  55     Lisp_Object command_channel_p;
  56     /* t if this is a real child process.
  57        For a net connection, it is (HOST SERVICE).  */
  58     Lisp_Object childp;
  59     /* Marker set to end of last buffer-inserted output from this process */
  60     Lisp_Object mark;
  61     /* Non-nil means kill silently if Emacs is exited.  */
  62     Lisp_Object kill_without_query;
  63     /* Record the process status in the raw form in which it comes from `wait'.
  64        This is to avoid consing in a signal handler.  */
  65     Lisp_Object raw_status_low;
  66     Lisp_Object raw_status_high;
  67     /* Symbol indicating status of process.
  68        This may be a symbol: run, open, or closed.
  69        Or it may be a list, whose car is stop, exit or signal
  70        and whose cdr is a pair (EXIT_CODE . COREDUMP_FLAG)
  71        or (SIGNAL_NUMBER . COREDUMP_FLAG).  */
  72     Lisp_Object status;
  73     /* Non-nil if communicating through a pty.  */
  74     Lisp_Object pty_flag;
  75     /* Event-count of last event in which this process changed status.  */
  76     Lisp_Object tick;
  77     /* Event-count of last such event reported.  */
  78     Lisp_Object update_tick;
  79     /* Coding-system for decoding the input from this process.  */
  80     Lisp_Object decode_coding_system;
  81     /* Working buffer for decoding.  */
  82     Lisp_Object decoding_buf;
  83     /* Size of carryover in decoding.  */
  84     Lisp_Object decoding_carryover;
  85     /* Coding-system for encoding the output to this process.  */
  86     Lisp_Object encode_coding_system;
  87     /* Working buffer for encoding.  */
  88     Lisp_Object encoding_buf;
  89     /* Size of carryover in encoding.  */
  90     Lisp_Object encoding_carryover;
  91     /* Flag to set coding-system of the process buffer from the
  92        coding_system used to decode process output.  */
  93     Lisp_Object inherit_coding_system_flag;
  94 };
  95
  96 /* Every field in the preceding structure except for the first two
  97    must be a Lisp_Object, for GC's sake.  */
  98
  99 #define ChannelMask(n) (1<<(n))
 100
 101 /* Indexed by descriptor, gives the process (if any) for that descriptor.  */
 102 extern Lisp_Object chan_process[];
 103
 104 /* Alist of elements (NAME . PROCESS).  */
 105 extern Lisp_Object Vprocess_alist;
 106
 107 /* True iff we are about to fork off a synchronous process or if we
 108    are waiting for it.  */
 109 extern int synch_process_alive;
 110
 111 /* Communicate exit status of sync process to from sigchld_handler
 112    to Fcall_process.  */
 113
 114 /* Nonzero => this is a string explaining death of synchronous subprocess.  */
 115 extern char *synch_process_death;
 116
 117 /* If synch_process_death is zero,
 118    this is exit code of synchronous subprocess.  */
 119 extern int synch_process_retcode;
 120
 121 /* The name of the file open to get a null file, or a data sink.
 122    VMS, MS-DOS, and OS/2 redefine this.  */
 123 #ifndef NULL_DEVICE
 124 #define NULL_DEVICE "/dev/null"
 125 #endif