[Slackbuilds-users] Problem/fix for SlackBuild for MP3Diags

[B. Watson]

Replying directly to the poster, plus to the list.

On Wed, 12 Apr 2023, David Halliwell wrote:

>    Today, I wanted to build/install the MP3Diags software (https://slackbuilds.org/repository/15.0/audio/MP3Diags/?search=mp3diag). It would not
> build, exiting with a message about not finding Qwidget. I had seen the qt4 dependency, and had downloaded, built, and installed qt4 using he
> Slackbuild, but MP3Diags would not build on my Slackware 15.0 system (upgraded last year from 14.2). I also tried building it on a fairly clean
> Slackware 15.0 VM, but had the same error.

The probable reason for a SlackBuild not picking up your qt4 is
that qt4 installs a script that sets some environment variables, in
/etc/profile.d/. If you didn't have qt4 already installed, and you
install it, then try to build something that expects those variables
to already be set... you get the exact issue you were having.

The easiest thing to do is install qt4, then log out & back in. Your
new login will have the environment variables set correctly. The qt4
README doesn't actually mention this (though it should).

It's possible to write a SlackBuild that will source the profile
script itself, avoiding this problem, but not all qt4-using scripts do
this. You've found one that doesn't, apparently.

So yeah, the MP3Diags SlackBuild needs attention. And so does the
README for qt4. Thanks for pointing it out.