/*
* If a lock is already taken for the file, `die()` with an error
* message. If this flag is not specified, trying to lock a file that
- * is already locked returns -1 to the caller.
+ * is already locked silently returns -1 to the caller, or ...
*/
#define LOCK_DIE_ON_ERROR 1
+/*
+ * ... this flag can be passed instead to return -1 and give the usual
+ * error message upon an error.
+ */
+#define LOCK_REPORT_ON_ERROR 4
+
/*
* Usually symbolic links in the destination path are resolved. This
* means that (1) the lockfile is created by adding ".lock" to the