dwm-nest/util.c

55 lines
1.0 KiB
C

/* (C)opyright MMVI-MMVII Anselm R. Garbe <garbeam at gmail dot com>
* See LICENSE file for license details.
*/
#include "dwm.h"
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
/* extern */
void *
emallocz(unsigned int size) {
void *res = calloc(1, size);
if(!res)
eprint("fatal: could not malloc() %u bytes\n", size);
return res;
}
void
eprint(const char *errstr, ...) {
va_list ap;
va_start(ap, errstr);
vfprintf(stderr, errstr, ap);
va_end(ap);
exit(EXIT_FAILURE);
}
void
spawn(Arg arg) {
static char *shell = NULL;
if(!shell && !(shell = getenv("SHELL")))
shell = "/bin/sh";
if(!arg.cmd)
return;
/* The double-fork construct avoids zombie processes and keeps the code
* clean from stupid signal handlers. */
if(fork() == 0) {
if(fork() == 0) {
if(dpy)
close(ConnectionNumber(dpy));
setsid();
execl(shell, shell, "-c", arg.cmd, (char *)NULL);
fprintf(stderr, "dwm: execl '%s -c %s'", shell, arg.cmd);
perror(" failed");
}
exit(0);
}
wait(0);
}