Import initial version of the client

1 files changed, 21 insertions, 0 deletions

diff --git a/client/utils/locking.py b/client/utils/locking.py
new file mode 100644
index 0000000..dfc8f63
--- /dev/null
+++ b/client/utils/locking.py
@@ -0,0 +1,21 @@
+import fcntl
+import os
+
+
+class FileLock():
+	'a simple wrapper around file lock'
+
+	def __init__(self, filename):
+		self._file = open(filename, 'w')
+
+	def __enter__(self):
+		'locks the file and writes the PID of the current process into it'
+		fcntl.flock(self._file, fcntl.LOCK_EX)
+		self._file.write(str(os.getpid()))
+		self._file.flush()
+
+		return self._file
+
+	def __exit__(self, type, value, traceback):
+		'unlock the file'
+		fcntl.flock(self._file, fcntl.LOCK_UN)