debian/rules and find

[Martin Schulze <joey@finlandia.Infodrom.North.DE>]

Hi,

this afternoon I occurred a serious problem where some of our
debian/rules file will fail.

xargs will *always* execute the command, even with no input.  This
means that all constructs like "find -name foo|xargs chmod g+w" will
fail as soon as find doesn't find any file.  As Joey pointed out this
is a documented feature.  I understand that there are situations where
this is a needed feature.

However in the process of creating .deb files this is not needed, even
worse it will stop the creation.  Instead we should use xargs -r or
--no-run-if-empty which won't execute the program on the command line
if there is no input.

So please check your debian/rules files for constructs like the
following:

       chmod g+w `find debian/tmp -name foo`

       find debian/tmp -name foo|xargs chmod g+w

the correct way to implement this would be

       find debian/tmp -name foo|xargs -r chmod g+w

Regards,

	Joey

-- 
There are lies, statistics and benchmarks.