src/process.h

   1 /* Definitions for asynchronous process control in GNU Emacs.
   2    Copyright (C) 1985, 1994, 2002, 2003, 2004,
   3                  2005, 2006 Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   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 2, or (at your option)
  10 any later version.
  11
  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.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22
  23 /* This structure records information about a subprocess
  24    or network connection.
  25
  26    Every field in this structure except for the first two
  27    must be a Lisp_Object, for GC's sake.  */
  28
  29 struct Lisp_Process
  30   {
  31     EMACS_INT size;
  32     struct Lisp_Vector *v_next;
  33     /* Descriptor by which we read from this process */
  34     Lisp_Object infd;
  35     /* Descriptor by which we write to this process */
  36     Lisp_Object outfd;
  37     /* Name of subprocess terminal.  */
  38     Lisp_Object tty_name;
  39     /* Name of this process */
  40     Lisp_Object name;
  41     /* List of command arguments that this process was run with.
  42        Is set to t for a stopped network process; nil otherwise. */
  43     Lisp_Object command;
  44     /* (funcall FILTER PROC STRING)  (if FILTER is non-nil)
  45        to dispose of a bunch of chars from the process all at once */
  46     Lisp_Object filter;
  47     /* (funcall SENTINEL PROCESS) when process state changes */
  48     Lisp_Object sentinel;
  49     /* (funcall LOG SERVER CLIENT MESSAGE) when a server process
  50        accepts a connection from a client.  */
  51     Lisp_Object log;
  52     /* Buffer that output is going to */
  53     Lisp_Object buffer;
  54     /* t if this is a real child process.
  55        For a net connection, it is a plist based on the arguments to make-network-process.  */
  56     Lisp_Object childp;
  57     /* Plist for programs to keep per-process state information, parameters, etc.  */
  58     Lisp_Object plist;
  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        This is the inverse of the `query-on-exit' flag.  */
  63     Lisp_Object kill_without_query;
  64     /* Symbol indicating status of process.
  65        This may be a symbol: run, open, or closed.
  66        Or it may be a list, whose car is stop, exit or signal
  67        and whose cdr is a pair (EXIT_CODE . COREDUMP_FLAG)
  68        or (SIGNAL_NUMBER . COREDUMP_FLAG).  */
  69     Lisp_Object status;
  70     /* Non-nil if communicating through a pty.  */
  71     Lisp_Object pty_flag;
  72     /* Event-count of last event in which this process changed status.  */
  73     Lisp_Object tick;
  74     /* Event-count of last such event reported.  */
  75     Lisp_Object update_tick;
  76     /* Coding-system for decoding the input from this process.  */
  77     Lisp_Object decode_coding_system;
  78     /* Working buffer for decoding.  */
  79     Lisp_Object decoding_buf;
  80     /* Size of carryover in decoding.  */
  81     Lisp_Object decoding_carryover;
  82     /* Coding-system for encoding the output to this process.  */
  83     Lisp_Object encode_coding_system;
  84     /* Working buffer for encoding.  */
  85     Lisp_Object encoding_buf;
  86     /* Size of carryover in encoding.  */
  87     Lisp_Object encoding_carryover;
  88     /* Flag to set coding-system of the process buffer from the
  89        coding_system used to decode process output.  */
  90     Lisp_Object inherit_coding_system_flag;
  91     /* Flat to decide the multibyteness of a string given to the
  92        filter (if any).  It is initialized to the value of
  93        `default-enable-multibyte-characters' when the process is
  94        generated, and can be changed by the function
  95        `set-process-fileter-multibyte'. */
  96     Lisp_Object filter_multibyte;
  97     /* Should we delay reading output from this process.
  98        Initialized from `Vprocess_adaptive_read_buffering'.  */
  99     Lisp_Object adaptive_read_buffering;
 100     /* Hysteresis to try to read process output in larger blocks.
 101        On some systems, e.g. GNU/Linux, Emacs is seen as
 102        an interactive app also when reading process output, meaning
 103        that process output can be read in as little as 1 byte at a
 104        time.  Value is micro-seconds to delay reading output from
 105        this process.  Range is 0 .. 50000.  */
 106     Lisp_Object read_output_delay;
 107     /* Skip reading this process on next read.  */
 108     Lisp_Object read_output_skip;
 109
 110     /* After this point, there are no Lisp_Objects any more.  */
 111
 112     /* Number of this process.
 113        allocate_process assumes this is the first non-Lisp_Object field.
 114        A value 0 is used for pseudo-processes such as network connections.  */
 115     pid_t pid;
 116     /* Record the process status in the raw form in which it comes from `wait'.
 117        This is to avoid consing in a signal handler.  The `raw_status_new'
 118        flag indicates that `raw_status' contains a new status that still
 119        needs to be synced to `status'.  */
 120     int raw_status_new : 1;
 121     int raw_status;
 122 };
 123
 124 /* Every field in the preceding structure except for the first two
 125    must be a Lisp_Object, for GC's sake.  */
 126
 127 #define ChannelMask(n) (1<<(n))
 128
 129 /* Indexed by descriptor, gives the process (if any) for that descriptor.  */
 130 extern Lisp_Object chan_process[];
 131
 132 /* Alist of elements (NAME . PROCESS).  */
 133 extern Lisp_Object Vprocess_alist;
 134
 135 /* True iff we are about to fork off a synchronous process or if we
 136    are waiting for it.  */
 137 extern int synch_process_alive;
 138
 139 /* Communicate exit status of sync process to from sigchld_handler
 140    to Fcall_process.  */
 141
 142 /* Nonzero => this is a string explaining death of synchronous subprocess.  */
 143 extern char *synch_process_death;
 144
 145 /* Nonzero => this is the signal number that terminated the subprocess.  */
 146 extern int synch_process_termsig;
 147
 148 /* If synch_process_death is zero,
 149    this is exit code of synchronous subprocess.  */
 150 extern int synch_process_retcode;
 151
 152 /* The name of the file open to get a null file, or a data sink.
 153    VMS, MS-DOS, and OS/2 redefine this.  */
 154 #ifndef NULL_DEVICE
 155 #define NULL_DEVICE "/dev/null"
 156 #endif
 157
 158 /* arch-tag: dffedfc4-d7bc-4b58-a26f-c16155449c72
 159    (do not change this comment) */