gzip tries to unpack/pack 1st the filename of $GZIP

[Steve Randall]

On Thu, 14 Oct 2010 10:36:59 +0200
Matthias Apitz <guru at unixarea.de> wrote:

> 
> Hello,
> 
> I was facing a problem in some Makefile/shell-scripting and finally I
> could nail it down:
> 
> when you set the environment variable GZIP to something, for example to
> let it point to gzip itself, it tries 1st to unpack this file:
> 
> $ GZIP=/usr/bin/gzip export GZIP
> $ $GZIP -dc source.tar.gz | wc -l
> gzip: /usr/bin/gzip: not in gzip format
>   645770
> 
> o
> 
> $ GZIP=bla export GZIP
> $ gzip -dc source.tar.gz | wc -l
> gzip: can't stat: bla: No such file or directory
>   645770
> 
> Why is this? It's not mentioned in the man page.

It is, actually.

ENVIRONMENT
     If the environment variable GZIP is set, it is parsed as a white-space
     separated list of options handled before any options on the command line.