--- /dev/null
+/*
+ * $Id: lock.c,v 1.1 2002/01/22 16:03:02 dfs 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
+