Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.python > #6273

Re: Python 3.2 bug? Reading the last line of a file

From "tkpmep@hotmail.com" <tkpmep@hotmail.com>
Newsgroups comp.lang.python
Subject Re: Python 3.2 bug? Reading the last line of a file
Date 2011-05-25 16:25 -0700
Organization http://groups.google.com
Message-ID <55262a36-ca53-48dd-b563-1847f9442bae@dn9g2000vbb.googlegroups.com> (permalink)
References <3d81e2a0-6c86-4f12-a1c4-ce4c736172b6@y31g2000vbp.googlegroups.com> <4DDD5FD2.8040607@mrabarnett.plus.com> <BANLkTik1NyMO8vEfb-+oO_7jLD9B=+ZMRA@mail.gmail.com> <mailman.2096.1306360361.9059.python-list@python.org>

Show all headers | View raw


Thanks for the guidance - it was indeed an issue with reading in
binary vs. text., and I do now succeed in reading the last line,
except that I now seem unable to split it, as I demonstrate below.
Here's what I get when I read the last line in text mode using 2.7.1
and in binary mode using 3.2 respectively under IDLE:

2.7.1
Name	31/12/2009	0	0	0

3.2
b'Name\t31/12/2009\t0\t0\t0\r\n'

if, under 2.7.1 I read the file in text mode and write
>>> x = lastLine(fn)
I can then cleanly split the line to get its contents
>>> x.split('\t')
['Name', '31/12/2009', '0', '0', '0\n']

but under 3.2, with its binary read, I get
>>> x.split('\t')
Traceback (most recent call last):
  File "<pyshell#26>", line 1, in <module>
    x.split('\t')
TypeError: Type str doesn't support the buffer API

If I remove the '\t', the split now works and I get a list of bytes
literals
>>> x.split()
[b'Name', b'31/12/2009', b'0', b'0', b'0']

Looking through the docs did not clarify my understanding of the
issue. Why can I not split on '\t' when reading in binary mode?

Sincerely

Thomas Philips

Back to comp.lang.python | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

Python 3.2 bug? Reading the last line of a file "tkpmep@hotmail.com" <tkpmep@hotmail.com> - 2011-05-25 12:33 -0700
  Re: Python 3.2 bug? Reading the last line of a file MRAB <python@mrabarnett.plus.com> - 2011-05-25 21:00 +0100
  Re: Python 3.2 bug? Reading the last line of a file Ian Kelly <ian.g.kelly@gmail.com> - 2011-05-25 14:54 -0600
  Re: Python 3.2 bug? Reading the last line of a file MRAB <python@mrabarnett.plus.com> - 2011-05-25 22:52 +0100
    Re: Python 3.2 bug? Reading the last line of a file "tkpmep@hotmail.com" <tkpmep@hotmail.com> - 2011-05-25 16:25 -0700
      Re: Python 3.2 bug? Reading the last line of a file Ethan Furman <ethan@stoneleaf.us> - 2011-05-25 16:58 -0700
      Re: Python 3.2 bug? Reading the last line of a file MRAB <python@mrabarnett.plus.com> - 2011-05-26 00:56 +0100
      Re: Python 3.2 bug? Reading the last line of a file Ethan Furman <ethan@stoneleaf.us> - 2011-05-25 17:32 -0700
      Re: Python 3.2 bug? Reading the last line of a file Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2011-05-26 08:09 +0300
        Re: Python 3.2 bug? Reading the last line of a file "tkpmep@hotmail.com" <tkpmep@hotmail.com> - 2011-05-27 12:21 -0700
  Re: Python 3.2 bug? Reading the last line of a file Ian Kelly <ian.g.kelly@gmail.com> - 2011-05-25 19:06 -0600

csiph-web