> -----Original Message----- > From: MRAB [mailto:goo...@mrabarnett.plus.com] > Sent: Thursday, May 21, 2009 19:02 > To: 'python-list@python.org' > Subject: Re: A fast way to read last line of gzip archive ? > > Barak, Ron wrote: > > Hi, > > > > I need to read the end of a 20 MB gzip archives (To extract > the date > > from the last line of a a gzipped log file). > > The solution I have below takes noticeable time to reach the end of > > the gzip archive. > > > > Does anyone have a faster solution to read the last line of > a gzip archive ? > > > > Thanks, > > Ron. > > > > #!/usr/bin/env python > > > > import gzip > > > > path = "./a/20/mb/file.tgz" > > > > in_file = gzip.open(path, "r") > > first_line = in_file.readline() > > print "first_line ==",first_line > > in_file.seek(-500) > > last_line = in_file.readlines()[-1] > > print "last_line ==",last_line > > > It takes a noticeable time to reach the end because, well, > the data is compressed! The compression method used requires > the preceding data to be read first.
I thought maybe someone has a way to unzip just the end portion of the archive (instead of the whole archive), as only the last part is needed for reading the last line. Bye, Ron. -- http://mail.python.org/mailman/listinfo/python-list
