--- Repo.py.~1.24.~	2006-05-20 16:46:57.000000000 +0200
+++ Repo.py	2006-05-20 16:47:08.000000000 +0200
@@ -196,6 +196,14 @@
 
     def _update_repo(self):
         """ Copy new RPMS to the repo, and updates the repo at the end """
+        # Lock repo lockfile.
+        lockfilename = '.repo-update.lock'
+        lockfile = open(os.path.join(self._repodir,lockfilename),'w')
+        try:
+            rc = fcntl.flock(lockfile,fcntl.LOCK_EX)
+        except IOError (errno, strerr):
+            print 'ERROR: %s: %s' % (strerr,lockfilename)
+        
         for buildjob in self._repo_additions:
             # Ensure all the files are accessible
             success = True
@@ -228,6 +236,9 @@
         (s, o) = commands.getstatusoutput('/usr/bin/createrepo -q -c %s -x "*.src.rpm" -x "*-debuginfo-*" %s' % (self._repo_cache_dir, self._repodir))
         if s != 0:
             print "Repo Error (%s): createrepo failed with exit status %d!  Output: '%s'" % (self._target_cfg.target_string(), s, o)
+        # Unlock repo lockfile.
+        fcntl.flock(lockfile,fcntl.LOCK_UN)
+        lockfile.close()
 
     def _start_repo_script(self):
         target_str = self._target_cfg.target_string()