1/***********************************************************************
2*                                                                      *
3*               This software is part of the ast package               *
4*          Copyright (c) 1992-2011 AT&T Intellectual Property          *
5*                      and is licensed under the                       *
6*                  Common Public License, Version 1.0                  *
7*                    by AT&T Intellectual Property                     *
8*                                                                      *
9*                A copy of the License is available at                 *
10*            http://www.opensource.org/licenses/cpl1.0.txt             *
11*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12*                                                                      *
13*              Information and Software Systems Research               *
14*                            AT&T Research                             *
15*                           Florham Park NJ                            *
16*                                                                      *
17*                 Glenn Fowler <gsf@research.att.com>                  *
18*                  David Korn <dgk@research.att.com>                   *
19*                                                                      *
20***********************************************************************/
21#pragma prototyped
22
23#define FORMAT		"PID=%(pid)d PPID=%(ppid)d PGID=%(pgid)d TID=%(tid)d SID=%(sid)d"
24
25static const char usage[] =
26"[-?\n@(#)$Id: pids (AT&T Research) 2008-04-01 $\n]"
27USAGE_LICENSE
28"[+NAME?pids - list calling shell process ids]"
29"[+DESCRIPTION?When invoked as a shell builtin, \bpids\b lists one or "
30    "more of the calling process ids determined by \bgetpid\b(2), "
31    "\bgetppid\b(2), \bgetpgrp\b(2), \btcgetpgrp\b(2) and \bgetsid\b(2). "
32    "Unknown or invalid ids have the value \b-1\b.]"
33"[f:format?List the ids specified by \aformat\a. \aformat\a follows "
34    "\bprintf\b(3) conventions, except that \bsfio\b(3) inline ids are used "
35    "instead of arguments: "
36    "%[-+]][\awidth\a[.\aprecis\a[.\abase\a]]]]]](\aid\a)\achar\a. The "
37    "supported \aid\as are:]:[format:=" FORMAT "]"
38    "{"
39        "[+pid?The process id.]"
40        "[+pgid?The process group id.]"
41        "[+ppid?The parent process id.]"
42        "[+tid|tty?The controlling terminal id.]"
43        "[+sid?The session id.]"
44    "}"
45"[+SEE ALSO?\bgetpid\b(2), \bgetppid\b(2), \bgetpgrp\b(2), "
46    "\btcgetpgrp\b(2), \bgetsid\b(2)]"
47;
48
49#include <cmd.h>
50#include <ast_tty.h>
51#include <sfdisc.h>
52
53/*
54 * sfkeyprintf() lookup
55 * handle==0 for heading
56 */
57
58static int
59key(void* handle, Sffmt_t* fp, const char* arg, char** ps, Sflong_t* pn)
60{
61	register char*	s;
62	int		fd;
63	long		tid;
64
65	if (!(s = fp->t_str) || streq(s, "pid"))
66		*pn = getpid();
67	else if (streq(s, "pgid"))
68		*pn = getpgid(0);
69	else if (streq(s, "ppid"))
70		*pn = getppid();
71	else if (streq(s, "tid") || streq(s, "tty"))
72	{
73		for (fd = 0; fd < 3; fd++)
74			if ((tid = tcgetpgrp(fd)) >= 0)
75				break;
76		*pn = tid;
77	}
78	else if (streq(s, "sid"))
79		*pn = getsid(0);
80	else if (streq(s, "format"))
81		*ps = (char*)handle;
82	else
83	{
84		error(2, "%s: unknown format identifier", s);
85		return 0;
86	}
87	return 1;
88}
89
90int
91b_pids(int argc, char** argv, void* context)
92{
93	char*			format = 0;
94
95	cmdinit(argc, argv, context, ERROR_CATALOG, 0);
96	for (;;)
97	{
98		switch (optget(argv, usage))
99		{
100		case 'f':
101			format = opt_info.arg;
102			continue;
103		case '?':
104			error(ERROR_USAGE|4, "%s", opt_info.arg);
105			break;
106		case ':':
107			error(2, "%s", opt_info.arg);
108			break;
109		}
110		break;
111	}
112	argv += opt_info.index;
113	if (error_info.errors || *argv)
114		error(ERROR_USAGE|4, "%s", optusage(NiL));
115	if (!format)
116		format = FORMAT;
117	sfkeyprintf(sfstdout, format, format, key, NiL);
118	sfprintf(sfstdout, "\n");
119	return 0;
120}
121