GNU bug report logs - #29648
BUG in zless and similar scripts?

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Michele Venturi <dardo82 <at> gmail.com>
To: bug-gzip <at> gnu.org
Subject: BUG in zless and similar scripts?
Date: Sun, 10 Dec 2017 10:26:32 +0100

[Message part 1 (text/plain, inline)]

As you can see here: https://pastebin.com/Q7fcrYhp
there is an error in the parameters expansion syntax.

It should be "${LESSMETACHARS:+set}" and not just
"${LESSMETACHARS+set}". zdiff, zgrep and zmore
miss a colon in the source code in the same way.
--
http://profiles.google.com/dardo82

[Message part 2 (text/html, inline)]

Message #8 received at 29648 <at> debbugs.gnu.org (full text, mbox):

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Michele Venturi <dardo82 <at> gmail.com>, 29648 <at> debbugs.gnu.org
Subject: Re: bug#29648: BUG in zless and similar scripts?
Date: Tue, 12 Dec 2017 16:58:26 -0800

On 12/10/2017 01:26 AM, Michele Venturi wrote:
> As you can see here:https://pastebin.com/Q7fcrYhp
> there is an error in the parameters expansion syntax.
>
> It should be "${LESSMETACHARS:+set}" and not just
> "${LESSMETACHARS+set}". zdiff, zgrep and zmore
> miss a colon in the source code in the same way.

Why is this a bug? I don't see the problem. Can you give an example of 
misbehavior because of the bug?

Perhaps the simplest fix for the bug, once we know what it is, would be 
to remove the workaround for less 394 and earlier, as I doubt whether 
anyone would combine a 'less' that old with new 'gzip'.

Message #11 received at 29648 <at> debbugs.gnu.org (full text, mbox):

From: Vidar Holen <vidar <at> vidarholen.net>
To: Paul Eggert <eggert <at> cs.ucla.edu>
Cc: 29648 <at> debbugs.gnu.org, Michele Venturi <dardo82 <at> gmail.com>
Subject: Re: bug#29648: BUG in zless and similar scripts?
Date: Tue, 12 Dec 2017 17:50:12 -0800

[Message part 1 (text/plain, inline)]

${var:+value} and ${var+value} differ in how they handle the case when
var="" (i.e. defined, and assigned the empty string).

In this case, the check verifies that LESSMETACHARS is set (even if it's
set to the empty string), so it seems correct as is.

On Tue, Dec 12, 2017 at 4:58 PM, Paul Eggert <eggert <at> cs.ucla.edu> wrote:

> On 12/10/2017 01:26 AM, Michele Venturi wrote:
>
>> As you can see here:https://pastebin.com/Q7fcrYhp
>> there is an error in the parameters expansion syntax.
>>
>> It should be "${LESSMETACHARS:+set}" and not just
>> "${LESSMETACHARS+set}". zdiff, zgrep and zmore
>> miss a colon in the source code in the same way.
>>
>
> Why is this a bug? I don't see the problem. Can you give an example of
> misbehavior because of the bug?
>
> Perhaps the simplest fix for the bug, once we know what it is, would be to
> remove the workaround for less 394 and earlier, as I doubt whether anyone
> would combine a 'less' that old with new 'gzip'.
>
>
>
>
>

[Message part 2 (text/html, inline)]

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