Logcheck devel - Jan 2005 - Bug#289801: Logtail should output error messages to stderr, not stdout

Package: logtail
Version: 1.2.33
Severity: normal

Hi...

Logtail should not output error messages to standard output, since this 
violates the principle of least surprise.

In particular, my application was broken by the semantics of logtail changing 
in version 1.2.21 (when you added switches for the default arguments to 
logtail). I think this was a bad move -- you broke an interface used by other 
people for no immediately apparent reason. logtail is _not_ only used by 
logcheck! Please consider other users of logtail next time you change 
something.

That notwithstanding, since logtail prints its error messages to standard 
output, the error message about the incorrect argument format is lost. One 
would expect the normal usage of logtail would have been something like:
logtail logfile offsetfile | some_program

With the new version of logtail, this produces an error message to standard 
output, which is then sent to 'some_program'. I would claim that the
correct
behaviour is to send the message to standard error, so logtail is not 
silently broken by installing logtail from sarge.

=)
Peter

Hi Peter

On Tue, Jan 11, 2005 at 04:03:22PM +1100, Peter Hawkins
wrote:
> Logtail should not output error messages to standard output, since this 
> violates the principle of least surprise.
Agreed!  I'll get a patch in shortly.
> In particular, my application was broken by the semantics of logtail
changing
> in version 1.2.21 (when you added switches for the default arguments to 
> logtail). I think this was a bad move -- you broke an interface used by
other
> people for no immediately apparent reason. logtail is _not_ only used by 
> logcheck! Please consider other users of logtail next time you change 
> something.
Agreed again.  I will pay more attention to this in the future.  I am not
entirely sure why this was changed in the first place.

-- 
[   Todd J. Troxell                                         ,''`.
      Student, Debian GNU/Linux Developer, SysAdmin, Geek  : :' :
      http://debian.org || http://rapidpacket.com/~xtat    `. `' 
                                                             `-     ]
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Your message dated Sun, 23 Jan 2005 22:02:06 -0500
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and subject line Bug#289801: fixed in logcheck 1.2.34
has caused the attached Bug report to be marked as done.

This means that you claim that the problem has been dealt with.
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Bug report if necessary, and/or fix the problem forthwith.

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Subject: Logtail should output error messages to stderr, not stdout
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Package: logtail
Version: 1.2.33
Severity: normal

Hi...

Logtail should not output error messages to standard output, since this 
violates the principle of least surprise.

In particular, my application was broken by the semantics of logtail changing 
in version 1.2.21 (when you added switches for the default arguments to 
logtail). I think this was a bad move -- you broke an interface used by other 
people for no immediately apparent reason. logtail is _not_ only used by 
logcheck! Please consider other users of logtail next time you change 
something.

That notwithstanding, since logtail prints its error messages to standard 
output, the error message about the incorrect argument format is lost. One 
would expect the normal usage of logtail would have been something like:
logtail logfile offsetfile | some_program

With the new version of logtail, this produces an error message to standard 
output, which is then sent to 'some_program'. I would claim that the
correct
behaviour is to send the message to standard error, so logtail is not 
silently broken by installing logtail from sarge.

=)
Peter

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From: Todd Troxell <ttroxell at debian.org>
To: 289801-close at bugs.debian.org
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Subject: Bug#289801: fixed in logcheck 1.2.34
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Source: logcheck
Source-Version: 1.2.34

We believe that the bug you reported is fixed in the latest version of
logcheck, which is due to be installed in the Debian FTP archive:

logcheck-database_1.2.34_all.deb
  to pool/main/l/logcheck/logcheck-database_1.2.34_all.deb
logcheck_1.2.34.dsc
  to pool/main/l/logcheck/logcheck_1.2.34.dsc
logcheck_1.2.34.tar.gz
  to pool/main/l/logcheck/logcheck_1.2.34.tar.gz
logcheck_1.2.34_all.deb
  to pool/main/l/logcheck/logcheck_1.2.34_all.deb
logtail_1.2.34_all.deb
  to pool/main/l/logcheck/logtail_1.2.34_all.deb



A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 289801 at bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Todd Troxell <ttroxell at debian.org> (supplier of updated logcheck
package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster at debian.org)


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Format: 1.7
Date: Sunday, 23 Jan 2005 21:31:00 -0500
Source: logcheck
Binary: logcheck logtail logcheck-database
Architecture: source all
Version: 1.2.34
Distribution: unstable
Urgency: low
Maintainer: Debian logcheck Team <logcheck-devel at
lists.alioth.debian.org>
Changed-By: Todd Troxell <ttroxell at debian.org>
Description: 
 logcheck   - Mails anomalies in the system logfiles to the administrator
 logcheck-database - A database of system log rules for the use of log checkers
 logtail    - Print log file lines that have not been read
Closes: 289529 289801 289866 290195 290511 291395
Changes: 
 logcheck (1.2.34) unstable; urgency=low
 .
   todd:
   * Correct "Gandhi" spelling in docs/README.how.to.interpret.
     Thanks Satya <debbugs at thesatya.com> (closes: #289529)
   * Set logtail to report errors on stderr instead of stdout.
     (closes: #289801)
   * Adjust logcheck to redirect stdout and also stderr when reporting in order
     to maintain the current behavior of logcheck after the change above.
   * Change rule directories to setgid for real this time. (closes: #291395)
   * Update gconf, workstation/kernel rules
   maks:
   * Add pdns, fix scponly, fix gconfd SIGHUP rule.
   * Fix pam_winbind rule at level workstation. (Closes: #289866)
   * Ignore sudo "command continued" logline. (Closes: #290195)
   * Add rule for daily sysklogd -r restart at level server. (Closes: #290511)
   jamie:
   * Update rules for nagios.
Files: 
 6612f3aae699b008fbbce64951b28d74 703 admin optional logcheck_1.2.34.dsc
 1042830c8ae783c69751fc99b588f943 90068 admin optional logcheck_1.2.34.tar.gz
 6cd0126e9f140a2dbaf22d28b5ce08d6 42210 admin optional logcheck_1.2.34_all.deb
 5fc7d09450a439eb169010993c84ac9b 57956 admin optional
logcheck-database_1.2.34_all.deb
 2426337abec798ed7a28ee5954f8717c 25770 admin optional logtail_1.2.34_all.deb

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