1 /* Copyright (C) 1991, 1992, 1995, 1996 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Library General Public License as
6 published by the Free Software Foundation; either version 2 of the
7 License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
14 You should have received a copy of the GNU Library General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If
16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
17 Cambridge, MA 02139, USA. */
26 /* Execute FILE, searching in the `PATH' environment variable if it contains
27 no slashes, with arguments ARGV and environment from `environ'. */
33 void execute (const char *file, char *const argv[])
39 /* The file is accessible but it is not an executable file.
40 Invoke the shell to interpret it as a script. */
45 /* Count the arguments. */
46 for (argc = 0; argv[argc++];);
48 /* Construct an argument list for the shell. */
49 new_argv = __alloca ((argc + 1) * sizeof (char *));
50 for (new_argv[0] = _PATH_BSHELL; argc > 0; --argc)
51 new_argv[argc] = argv[argc - 1];
53 /* Execute the shell. */
54 execv (new_argv[0], new_argv);
58 if (strchr (file, '/') != NULL)
59 /* Don't search when it contains a slash. */
63 char *path, *p, *name;
66 path = getenv ("PATH");
69 /* There is no `PATH' in the environment.
70 The default search path is the current directory
71 followed by the path `confstr' returns for `_CS_PATH'. */
72 len = confstr (_CS_PATH, (char *) NULL, 0);
73 path = (char *) __alloca (1 + len);
75 (void) confstr (_CS_PATH, path + 1, len);
78 len = strlen (file) + 1;
79 name = __alloca (strlen (path) + len);
84 p = strchr (path, ':');
86 p = strchr (path, '\0');
89 /* Two adjacent colons, or a colon at the beginning or the end
90 of `PATH' means to search the current directory. */
91 (void) memcpy (name, file, len);
94 /* Construct the pathname to try. */
95 (void) memcpy (name, path, p - path);
97 (void) memcpy (&name[(p - path) + 1], file, len);
100 /* Try to execute this name. If it works, execv will not return. */
101 execute (name, argv);
107 /* Those errors indicate the file is missing or not executable
108 by us, in which case we want to just try the next path
113 /* Some other error means we found an executable file, but
114 something went wrong executing it; return the error to our
119 while (*p++ != '\0');
122 /* We tried every element and none of them worked.
123 Return the error from the last attempt (probably ENOENT). */