hush/coreutils/watch.c
Rob Landley 399d2b5c24 Rich Felker suggested removing dprintf() from watch, and one thing led to
another... This adds bb_xspawn() support, which does vfork/exec.  (I don't
know why using a static instead of a local adds ~40 bytes, but using
the local doesn't work...)
2006-05-25 23:02:40 +00:00

69 lines
1.4 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini watch implementation for busybox
*
* Copyright (C) 2001 by Michael Habermann <mhabermann@gmx.de>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* BB_AUDIT SUSv3 N/A */
/* BB_AUDIT GNU defects -- only option -n is supported. */
/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
*
* Removed dependency on date_main(), added proper error checking, and
* reduced size.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <time.h>
#include <assert.h>
#include <unistd.h>
#include <sys/wait.h>
#include "busybox.h"
int watch_main(int argc, char **argv)
{
int width, len;
unsigned period = 2;
char **watched_argv, *header;
if (argc < 2) bb_show_usage();
get_terminal_width_height(1, &width, 0);
header = xzalloc(width--);
/* don't use getopt, because it permutes the arguments */
++argv;
if ((argc > 3) && !strcmp(*argv, "-n")) {
period = bb_xgetularg10_bnd(argv[1], 1, UINT_MAX);
argv += 2;
}
watched_argv = argv;
/* create header */
len = snprintf(header, width, "Every %ds:", period);
while (*argv && len<width)
snprintf(header+len, width-len, " %s", *(argv++));
while (1) {
char *thyme;
time_t t;
time(&t);
thyme = ctime(&t);
len = strlen(thyme);
if (len < width) header[width-len] = 0;
printf("\033[H\033[J%s %s\n", header, thyme);
waitpid(bb_xspawn(watched_argv),0,0);
sleep(period);
}
}