mes/lib/stdlib/system.c

60 lines
1.5 KiB
C

/* -*-comment-start: "//";comment-end:""-*-
* GNU Mes --- Maxwell Equations of Software
* Copyright © 2018,2022 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
*
* This file is part of GNU Mes.
*
* GNU Mes is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or (at
* your option) any later version.
*
* GNU Mes is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Mes. If not, see <http://www.gnu.org/licenses/>.
*/
#include <mes/lib.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
#ifndef SHELL_FILE_NAME
#define SHELL_FILE_NAME "/bin/sh"
#endif
#ifndef SHELL_COMMAND_NAME
#define SHELL_COMMAND_NAME "sh"
#endif
int
system (char const *command)
{
pid_t pid = fork ();
if (pid == -1)
return -1;
else if (pid == 0)
{
// child
char const *argv[4];
argv[0] = SHELL_COMMAND_NAME;
argv[1] = "-c";
argv[2] = command;
argv[3] = 0;
execve (SHELL_FILE_NAME, (char *const *) argv, environ);
_exit (127);
}
// parent
int status;
pid_t child_pid = waitpid (pid, &status, 0);
if (child_pid != pid)
return -1;
return status;
}