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/*
* This file is part of the sn package.
* Distribution of sn is covered by the GNU GPL. See file COPYING.
* Copyright 1998-2000 Harold Tay.
* Copyright 2000- Patrik Rdman.
*/
/*
* lockf() a file, for shell scripts.
*/
#include <unistd.h>
#include <string.h>
#include <out.h>
#include <format.h>
static const char rcsid[] = "$Id$";
int main (int argc, char **argv)
{
char *p;
char buffer[40];
progname = ((p = strrchr(argv[0], '/')) ? p + 1 : argv[0]);
if (argc != 1)
fail(1, "Usage: %s (no arguments or options)\n"
"%s always locks (using lockf()) descriptor 3, which should be open for writing.",
progname, progname);
if (lockf(3, F_TLOCK, 0) == -1)
_exit(2);
formats(buffer, 40, "%d\n", getpid()); /* Tell the script what our pid is, so it can kill us */
write(1, buffer, strlen(buffer));
fsync(1);
sleep(60 * 60);
_exit(0);
}
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