when doing signal functions (like sigaction) make sure it wasn't interrupted by a signal (errno==EINTR)

git-svn-id: https://svn.musicpd.org/mpd/trunk@729 09075e82-0dd4-0310-85a5-a0d7c8717e4f

src/directory.h

@@ -31,6 +31,8 @@ extern char directorydb[MAXPATHLEN+1];
 
 void readDirectoryDBIfUpdateIsFinished();
 
+void clearUpdatePid();
+
 int isUpdatingDB();
 
 void directory_sigChldHandler(int pid, int status);