The posixfile Module

(Obsolete, Unix only) The posixfile module provides a file-like object with support for file locking, as Example 14-27 shows. New programs should use the fcntl module instead.

Example 14-27. Using the posixfile Module

File: posixfile-example-1.py import posixfile import string filename = "counter.txt" try: # open for update file = posixfile.open(filename, "r+") counter = int(file.read(6)) + 1 except IOError: # create it file = posixfile.open(filename, "w") counter = 0 file.lock("w|", 6) file.seek(0) # rewind file.write("%06d" % counter) file.close() # releases lock