lib/prometheus/client/helper/file_locker.rb in prometheus-client-mmap-0.7.0.beta19 vs lib/prometheus/client/helper/file_locker.rb in prometheus-client-mmap-0.7.0.beta20

@@ -8,10 +8,10 @@
           def lock_to_process(filepath)
             LOCK_FILE_MUTEX.synchronize do
               @file_locks ||= {}
               return false if @file_locks[filepath]
 
-              file = File.open(filepath, 'w+')
+              file = File.open(filepath, 'ab')
               if file.flock(File::LOCK_NB | File::LOCK_EX)
                 @file_locks[filepath] = file
                 return true
               else
                 return false