/* cyr_lock.h -- file locking primitives
*
* Copyright (c) 1994-2008 Carnegie Mellon University. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The name "Carnegie Mellon University" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For permission or any legal
* details, please contact
* Carnegie Mellon University
* Center for Technology Transfer and Enterprise Creation
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*
* 4. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by Computing Services
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*
* CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
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*/
#ifndef INCLUDED_LOCK_H
#define INCLUDED_LOCK_H
#ifndef P
#ifdef __STDC__
#define P(x) x
#else
#define P(x) ()
#endif
#endif
#include <sys/stat.h>
extern const char *lock_method_desc;
extern int lock_reopen_ex(int fd, const char *filename,
struct stat *sbuf, const char **failaction,
int *changed);
#define lock_reopen(fd, filename, sbuf, failaction) \
lock_reopen_ex(fd, filename, sbuf, failaction, NULL)
extern int lock_setlock (int fd, int ex, int nb, const char *filename);
extern int lock_unlock (int fd, const char *filename);
/* compatibility defines for the older API */
#define lock_blocking(fd, fn) \
lock_setlock((fd), /*exclusive*/1, /*blocking*/0, (fn))
#define lock_nonblocking(fd, fn) \
lock_setlock((fd), /*exclusive*/1, /*nonblocking*/1, (fn))
#define lock_shared(fd, fn) \
lock_setlock((fd), /*exclusive*/0, /*nonblocking*/0, (fn))
#endif /* INCLUDED_LOCK_H */