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/*
* $Id: lock.c,v 1.1 1999/02/09 14:58:36 lf Exp $
*
* Copyright (C) 1997 Lars Fenneberg
*
* See the file COPYRIGHT for the respective terms and conditions.
* If the file is missing contact me at lf@elemental.net
* and I'll send you a copy.
*
*/
#include "config.h"
#include "includes.h"
#if defined(HAVE_FLOCK)
int do_lock_exclusive(int fd)
{
return flock(fd, LOCK_EX|LOCK_NB);
}
int do_unlock(int fd)
{
return flock(fd, LOCK_UN);
}
#elif defined(HAVE_FCNTL)
int do_lock_exclusive(int fd)
{
flock_t fl;
int res;
memset((void *)&fl, 0, sizeof(fl));
fl.l_type = F_WRLCK;
fl.l_whence = fl.l_start = 0;
fl.l_len = 0; /* 0 means "to end of file" */
res = fcntl(fd, F_SETLK, &fl);
if ((res == -1) && (errno == EAGAIN))
errno = EWOULDBLOCK;
return res;
}
int do_unlock(int fd)
{
flock_t fl;
memset((void *)&fl, 0, sizeof(fl));
fl.l_type = F_UNLCK;
fl.l_whence = fl.l_start = 0;
fl.l_len = 0; /* 0 means "to end of file" */
return fcntl(fd, F_SETLK, &fl);
}
#else
YOU_LOOSE "need either flock(2) or fcntl(2)"
#endif
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