GNU bug report logs - #33878
zcat vs zcat -f -- different output

Previous Next

Full log

Message #10 received at 33878-done <at> debbugs.gnu.org (full text, mbox):

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Namikaze Minato <lloydsensei <at> gmail.com>, 33878-done <at> debbugs.gnu.org
Subject: Re: bug#33878: zcat vs zcat -f -- different output
Date: Wed, 26 Dec 2018 10:03:57 -0800

Namikaze Minato wrote:

> Do you know what could be happening?

When gzip -cdf sees junk input data, it simply copies it to standard output; 
this behavior is documented in the gzip manual (look for --force). Your input 
files have NUL-byte padding at the end, contrary to Internet RFC 1952.

> Do you know how I could try to reproduce the problem on
> non-confidential data for you to be able to debug?

$ (gzip </dev/null; printf '\0') >t.gz
$ gzip -cd <t.gz | od -c
0000000
$ gzip -cdf <t.gz | od -c
0000000  \0
0000001

Though it's not a bug....

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.