Bug#288616: use of ">" in tetex postinst errors for sites using bash noclobber

[Hilmar Preusse <hille42@web.de>]

On 13.01.05 Frank Küster (frank@kuesterei.ch) wrote:
> "George Georgalis" <george@galis.org> wrote:
> > On Mon, Jan 10, 2005 at 02:31:54PM +0100, Frank K?ster wrote:
> >>"George Georgalis" <george@galis.org> wrote:

Hi George,

> >>> http://bugs.debian.org/275140
> >>>
> 
> Do you think that the postinst scripts are run with a login shell, or do
> you believe it? If you believe it, please give us some
> evidence. For example, put some echo command into ~/.bash_profile which
> is read by every login shell (we're speaking about bash, aren't we?) and
> show us that it is echoed when you do dpkg-reconfigure.
> 
> If it turns out that it does echo the message, we have to strace the
> call and look which files are actuall read. If again it turns out that
> it is not due to some misconfiguration on your system, but that dpkg
> calls it as a login shell, this is a bug in dpkg.
> 
> > I did find an exported BASH_ENV (which I don't normally use) in
> > ~root/.profile I did check before, but somehow I missed it.
> 
> So you mean this is the cause of the behavior you observed?
> 
> > There may be something else though, even with export BASH_ENV=$HOME/.bashrc
> > in $HOME/.profile and "set -o noclobber" in $HOME/.bashrc, I get the
> > following results:
> >
> > root@run:~/ # cat testclobber.sh
> > #/bin/bash
> > touch ~/testclobber.txt
> > echo >~/testclobber.txt
> > root@run:~/ # source testclobber.sh
> > bash: /root/testclobber.txt: cannot overwrite existing file
> > root@run:~/ # sh testclobber.sh
> > root@run:~/ # 
> 
> Try "bash testclobber.sh" instead.
> 
> > I think it illustrates the system only sets noclobber for login shells.
> 
> No, this just illustrates that you overlooked the following part from
> bash(1):
> 
> ,----
> | If bash is invoked with the name sh, it tries to mimic the startup
> | behavior of historical versions of sh as closely as possible, while
> | conforming to the POSIX standard as well. [...] A non-interactive
> | shell invoked with the name sh does not attempt to read any other
> | startup files. 
> `----
> 
> Note that this does not affect the shebang line; i.e. this compatibility
> mode is not used when you write #!/bin/sh in the first line of a script
> (I must admit that I don't know why).
> 
> > It would seem the apt-get/dpkg process invokes tetex.postinst as a login
> > shell, because of the noclobber error creating the temp file -- feel
> > free to correct me on this and I'll go away.
> 
> I have no indication that it does invoke it as a login shell, except
> that you report a problem with your noclobber setting. But it also seems
> that you didn't completely understand the startup behavior of bash (I
> also have to look it up always), so probably it *is* just a
> misconfiguration? 
> 
> > I'd appreciate >> vs > for writing to mktemp files on the next release.
> 
> You mean >|, or what?
> 
Frank Küster asked you some questions half a year ago, but you never
reacted. Do still intend to help us to track down the problem?  

Thanks,
 Hilmar
-- 
sigmentation fault