--- /dev/null
+/* ========================================================================
+ * Copyright 1988-2006 University of Washington
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *
+ * ========================================================================
+ */
+
+/*
+ * Program: Exclusive create of a file
+ *
+ * Author: Mark Crispin
+ * Networks and Distributed Computing
+ * Computing & Communications
+ * University of Washington
+ * Administration Building, AG-44
+ * Seattle, WA 98195
+ * Internet: MRC@CAC.Washington.EDU
+ *
+ * Date: 17 December 1999
+ * Last Edited: 30 August 2006
+ */
+\f
+/* Exclusive create of a file
+ * Accepts: file name
+ * Return: T if success, NIL if failed, -1 if retry
+ */
+
+long crexcl (char *name)
+{
+ int i;
+ int mask = umask (0);
+ long ret = LONGT;
+ /* try to get the lock */
+ if ((i = open (name,O_WRONLY|O_CREAT|O_EXCL,(int) shlock_mode)) < 0)
+ ret = (errno == EEXIST) ? -1 : NIL;
+ else close (i); /* made the file, now close it */
+ umask (mask); /* restore previous mask */
+ return LONGT; /* success */
+}