2 * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
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15 * documentation and/or other materials provided with the distribution.
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39 RCSID("$Id: flock.c,v 1.4 1999/12/02 16:58:46 joda Exp $");
44 #define OP_MASK (LOCK_SH | LOCK_EX | LOCK_UN)
47 flock(int fd, int operation)
49 #if defined(HAVE_FCNTL) && defined(F_SETLK)
53 arg.l_whence = SEEK_SET;
55 arg.l_len = 0; /* means to EOF */
57 if (operation & LOCK_NB)
60 cmd = F_SETLKW; /* Blocking */
62 switch (operation & OP_MASK) {
65 code = fcntl(fd, F_SETLK, &arg);
69 code = fcntl(fd, cmd, &arg);
73 code = fcntl(fd, cmd, &arg);