some (?) distributions define GDL_PATH. They should NOT AT ALL!

[GillesDuvert]

See #1992

The suse gdl installer creates a /etc/profile.d/gdl.csh that is not needed, AFAIK, and has adverse effects in the case of the solarsoft suite install.

Originally posted by @GillesDuvert in #1992 (comment)

[GillesDuvert]

Moreover we should add in share/gnudatalanguage a "bin/idl" link to the installed gdl so that:

1. when IDL_DIR points to ....../share/gnudatalanguage

2. any complicated script using IDL will

   1. find ....../share/gnudatalanguage/idl and call gdl
   2. find the lib/ and resources/ at the expected location, below IDL_DIR.

I'm sure @acoulais who also was involved in having NASA's solarsoft suite working with gdl will jump on these new infos! 😄

[GillesDuvert]

Sorry @olebole I wanted to attract the attention of the fedora manager, so it should be @opoplawski

[GillesDuvert]

@opoplawski apparently the openSuse is derived from fedora, and, apparently again, the 'gdl.sh' in the openSuse distro defining GDL_PATH comes from fedora...

[opoplawski]

What problems does setting GDL_PATH cause?

Without setting GDL_PATH, gdl does not find the functions in /usr/share/gnudatalanguage/lib, is that really what we want in a default install?

[gcomes]

I'm the current maintainer of gdl for openSUSE. I was contacted by GillesDuvert about the GDL_PATH issue and I went looking back in the changelog history of our package to identify when and why GDL_PATH was set. The openSUSE packages dates back to 2010 and when it was created was based on the fedora spec file. The fedora package started to set GDL_PATH in 2007 (fedora 5). I assume GDL_PATH was set in the openSUSE package because it was set in the fedora one. When I took over as package maintainer, I did try to figure out why GDL_PATH was set. Since I could not find a direct reference to why it was set, I assumed it was because it was necessary to find the functions in /usr/share/gnudatalanguage/lib. After GillesDuvert mentioned that setting GDL_PATH was not required, I did the following simple check:
If I start gdl with GDL_PATH set, I see the following message in the terminal:
Default library routine search path used (GDL_PATH/IDL_PATH env. var. not set): +/usr/share/gnudatalanguage
(note that the message claims that GDL_PATH is not set, but its value is used anyway).
If I start gdl without setting GDL_PATH (env -u GDL_PATH gdl), the following message appears:
Default library routine search path used (GDL_PATH/IDL_PATH env. var. not set): /usr/bin/../share/ gnudatalanguage/lib
While 18 years ago setting GDL_PATH was probably required to in order to find the functions in /usr/share/gnudatalanguage/lib, it looks like today that requirement is gone.
With the next release, the openSUSE package will not set anymore GDL_PATH.

[opoplawski]

Ah, thanks for that - it pointed out that I was not testing properly. I do see now that it works without GDL_PATH (and IDL_PATH) not set. I'll make the change in the Fedora package.