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#include <stdio.h>
#include <stddef.h>
#include <signal.h>
#include <unistd.h>
#include <sys/wait.h>
int system(command)
char *command;
{
int wait_val, pid;
__sighandler_t save_quit, save_int, save_chld;
if (command == 0)
return 1;
save_quit = signal(SIGQUIT, SIG_IGN);
save_int = signal(SIGINT, SIG_IGN);
save_chld = signal(SIGCHLD, SIG_DFL);
if ((pid = vfork()) < 0) {
signal(SIGQUIT, save_quit);
signal(SIGINT, save_int);
signal(SIGCHLD, save_chld);
return -1;
}
if (pid == 0) {
signal(SIGQUIT, SIG_DFL);
signal(SIGINT, SIG_DFL);
signal(SIGCHLD, SIG_DFL);
execl("/bin/sh", "sh", "-c", command, (char *) 0);
_exit(127);
}
/* Signals are not absolutly guarenteed with vfork */
signal(SIGQUIT, SIG_IGN);
signal(SIGINT, SIG_IGN);
printf("Waiting for child %d\n", pid);
if (wait4(pid, &wait_val, 0, 0) == -1)
wait_val = -1;
signal(SIGQUIT, save_quit);
signal(SIGINT, save_int);
signal(SIGCHLD, save_chld);
return wait_val;
}
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