exec.c revision 22997 
1#ifndef lint
2static const char *rcsid = "$Id$";
3#endif
4
5/*
6 * FreeBSD install - a package for the installation and maintainance
7 * of non-core utilities.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * Jordan K. Hubbard
19 * 18 July 1993
20 *
21 * Miscellaneous system routines.
22 *
23 */
24
25#include "lib.h"
26
27/*
28 * Unusual system() substitute.  Accepts format string and args,
29 * builds and executes command.  Returns exit code.
30 */
31
32int
33vsystem(const char *fmt, ...)
34{
35    va_list args;
36    char *cmd;
37    int ret, maxargs;
38
39    maxargs = sysconf(_SC_ARG_MAX);
40    maxargs -= 32;			/* some slop for the sh -c */
41    cmd = malloc(maxargs);
42    if (!cmd) {
43	whinge("vsystem can't alloc arg space");
44	return 1;
45    }
46
47    va_start(args, fmt);
48    if (vsnprintf(cmd, maxargs, fmt, args) > maxargs) {
49	whinge("vsystem args are too long");
50	return 1;
51    }
52#ifdef DEBUG
53printf("Executing %s\n", cmd);
54#endif
55    ret = system(cmd);
56    va_end(args);
57    free(cmd);
58    return ret;
59}
60
61