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/*
* Copyright (c) 1988 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that: (1) source distributions retain this entire copyright
* notice and comment, and (2) distributions including binaries display
* the following acknowledgement: ``This product includes software
* developed by the University of California, Berkeley and its contributors''
* in the documentation or other materials provided with the distribution
* and in all advertising materials mentioning features or use of this
* software. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifndef lint
static char sccsid[] = "@(#)uucplock.c 5.5 (Berkeley) 6/1/90";
#endif /* not lint */
#include <sys/types.h>
#include <sys/file.h>
#include <sys/dir.h>
#include <errno.h>
#define _PATH_LOCKDIRNAME "/usr/spool/uucp/LCK..%s"
extern char *sprintf();
/*
* uucp style locking routines
* return: 0 - success
* -1 - failure
*/
uu_lock(ttyname)
char *ttyname;
{
extern int errno;
int fd, pid;
char tbuf[sizeof(_PATH_LOCKDIRNAME) + MAXNAMLEN];
long lseek();
(void)sprintf(tbuf, _PATH_LOCKDIRNAME, ttyname);
fd = open(tbuf, O_RDWR|O_CREAT|O_EXCL, 0660);
if (fd < 0) {
/*
* file is already locked
* check to see if the process holding the lock still exists
*/
fd = open(tbuf, O_RDWR, 0);
if (fd < 0) {
/*perror("lock open");*/
return(-1);
}
if (read(fd, (char *)&pid, sizeof pid) != sizeof pid) {
(void)close(fd);
/*perror("lock read");*/
return(-1);
}
if (kill(pid, 0) == 0 || errno != ESRCH) {
(void)close(fd); /* process is still running */
return(-1);
}
/*
* The process that locked the file isn't running, so
* we'll lock it ourselves
*/
if (lseek(fd, 0L, L_SET) < 0) {
(void)close(fd);
/*perror("lock lseek");*/
return(-1);
}
/* fall out and finish the locking process */
}
pid = getpid();
if (write(fd, (char *)&pid, sizeof(pid)) != sizeof(pid)) {
(void)close(fd);
(void)unlink(tbuf);
/*perror("lock write");*/
return(-1);
}
(void)close(fd);
return(0);
}
uu_unlock(ttyname)
char *ttyname;
{
char tbuf[sizeof(_PATH_LOCKDIRNAME) + MAXNAMLEN];
(void)sprintf(tbuf, _PATH_LOCKDIRNAME, ttyname);
return(unlink(tbuf));
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.