1 /* 2 * $Id: lock.c,v 1.1 2004/11/14 07:26:26 paulus Exp $ 3 * 4 * Copyright (C) 1997 Lars Fenneberg 5 * 6 * See the file COPYRIGHT for the respective terms and conditions. 7 * If the file is missing contact me at lf (at) elemental.net 8 * and I'll send you a copy. 9 * 10 */ 11 12 #include "includes.h" 13 #include <unistd.h> 14 #include <fcntl.h> 15 16 int do_lock_exclusive(int fd) 17 { 18 struct flock fl; 19 int res; 20 21 memset((void *)&fl, 0, sizeof(fl)); 22 23 fl.l_type = F_WRLCK; 24 fl.l_whence = fl.l_start = 0; 25 fl.l_len = 0; /* 0 means "to end of file" */ 26 27 res = fcntl(fd, F_SETLK, &fl); 28 29 if ((res == -1) && (errno == EAGAIN)) 30 errno = EWOULDBLOCK; 31 32 return res; 33 } 34 35 int do_unlock(int fd) 36 { 37 struct flock fl; 38 39 memset((void *)&fl, 0, sizeof(fl)); 40 41 fl.l_type = F_UNLCK; 42 fl.l_whence = fl.l_start = 0; 43 fl.l_len = 0; /* 0 means "to end of file" */ 44 45 return fcntl(fd, F_SETLK, &fl); 46 } 47
