bzip2 refuses to work, attempts to create /opt/local/bin/bzip2.bz2 file

[mouse07410 (Mouse)]

When I try to bzip2 a file, I get this problem:

$ pwd
/Users/uri/src/ast61
$ ll Astro.txt
-r--r--r--  1 uri  staff  4620 Sep 11 11:42 Astro.txt
$ bzip2 Astro.txt 
bzip2: Can't create output file /opt/local/bin/bzip2.bz2: Permission denied.
$ ll Astro.txt*
-r--r--r--  1 uri  staff  2219 Sep 11 11:42 Astro.txt.bz2
$ bunzip2 Astro.txt.bz2 
bunzip2: Can't guess original name for /opt/local/bin/bzip2 -- using /opt/local/bin/bzip2.out
bunzip2: Output file /opt/local/bin/bzip2.out already exists.
$ ll Astro.txt*
-r--r--r--  1 uri  staff  4620 Sep 11 11:42 Astro.txt
$

While bzip2 does (usually - when not invoked from the script) create compressed file despite that complaint, it does not work when, e.g., bzip2 is invoked by GnuTAR:

$ gnutar -cjvf t.tbz Astro.txt
Astro.txt
bzip2: Can't create output file /opt/local/bin/bzip2.bz2: Permission denied.
gnutar: Child returned status 1
gnutar: Error is not recoverable: exiting now
$ ll t.tbz
-rw-r--r--  1 uri  staff  0 Sep 11 14:56 t.tbz
$ 

This bug (that I suspect is present in the upstream) prevents use of bzip2 - I'd appreciate your help.

[ryandesign (Ryan Carsten Schmidt)]

I've never seen anything like that before. It works fine for me:

$ echo hello > Astro.txt
$ ls -l Astro.txt*
-rw-r--r--  1 rschmidt  wheel  6 Sep 11 16:48 Astro.txt
$ bzip2 Astro.txt
$ ls -l Astro.txt*
-rw-r--r--  1 rschmidt  wheel  42 Sep 11 16:48 Astro.txt.bz2
$ bunzip2 Astro.txt.bz2
$ ls -l Astro.txt*
-rw-r--r--  1 rschmidt  wheel  6 Sep 11 16:48 Astro.txt
$ 

Sounds like a misconfiguration of some sort on your system. Maybe an alias or function overriding MacPorts bzip2.

What do you get when you run:

type bzip2
type bunzip2
bzip2 --version
bunzip2 --version

[mouse07410 (Mouse)]

Sounds like a misconfiguration of some sort on your system.

Based on what I'm observing, I rather doubt that - but would be happy to hear suggestions how to find this out.

Maybe an alias or function overriding MacPorts bzip2

I don't think so - see below.

What do you get when you run...

This:

$ type bzip2
bzip2 is hashed (/opt/local/bin/bzip2)
$ type bunzip2
bunzip2 is hashed (/opt/local/bin/bunzip2)
$ bzip2 --version
bzip2, a block-sorting file compressor.  Version 1.0.6, 6-Sept-2010.
   
   Copyright (C) 1996-2010 by Julian Seward.
   
   This program is free software; you can redistribute it and/or modify
   it under the terms set out in the LICENSE file, which is included
   in the bzip2-1.0.6 source distribution.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   LICENSE file for more details.
   
bzip2: Can't create output file /opt/local/bin/bzip2.bz2: Permission denied.
$ bunzip2 --version
bzip2, a block-sorting file compressor.  Version 1.0.6, 6-Sept-2010.
   
   Copyright (C) 1996-2010 by Julian Seward.
   
   This program is free software; you can redistribute it and/or modify
   it under the terms set out in the LICENSE file, which is included
   in the bzip2-1.0.6 source distribution.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   LICENSE file for more details.
   
bunzip2: Can't guess original name for /opt/local/bin/bzip2 -- using /opt/local/bin/bzip2.out
bunzip2: Can't create output file /opt/local/bin/bzip2.out: Permission denied.
$ alias bzip2
-bash: alias: bzip2: not found
$ alias bunzip2
-bash: alias: bunzip2: not found
$ 

[ryandesign (Ryan Carsten Schmidt)]

I've found a reference to a similar problem:

​https://lists.macosforge.org/pipermail/macports-changes/2014-April/103619.html

It suggests that you have set the BZIP2 environment variable to the path to the bzip2 program. But the bzip2 program actually uses that variable for additional arguments. So you should unset the BZIP2 environment variable.

[mouse07410 (Mouse)]

Yes!

I checked my .bashrc, and found

export BZIP2=/opt/local/bin/bzip2

in it (I don't remember what application needed that definition).

Then, after unsetting it:

$ unset BZIP2
$ bzip2 Astro.txt
$ bunzip2 Astro.txt.bz2 
$

So when env variable BZIP2 is not set, it works just fine. But why would that env var screw things up so badly? Isn't that a bug? What do you think?

[ryandesign (Ryan Carsten Schmidt)]

It's a documented feature of the bzip2 program. From its man page:

bzip2 will read arguments from the environment variables BZIP2 and BZIP, in that order, and will process them before any arguments read from the command line. This gives a convenient way to supply default arguments.

It was surprising to us too when we found out about this "feature" and we had to make some changes to MacPorts itself to not run into problems. We, too, had been using the BZIP2 environment variable as a way to specify the path to the bzip2 program, and had to change it.

[mouse07410 (Mouse)]

I see, thanks! Appreciate your time and help! And I've unseated BZIP2 now. ;-)