Preparation for Rocky Linux 9

This document describes requirements for Rocky Linux 9. To find your current release of RL 9, type: 
$ cat /etc/redhat-release
Rocky Linux release 9.2 (Blue Onyx)


Extra Fedora packages

First you need to add the The CodeReady Linux Builder (crb) repository which contains additional packages for use by developers. 
sudo dnf config-manager --set-enabled crb
sudo dnf install wget
sudo dnf install tcsh
sudo dnf install Xaw3d
sudo dnf install Xaw3d-devel
sudo dnf install libXaw-devel
sudo dnf install ncurses-devel
sudo dnf install gfortran


Python

The most convenient and functional way to provide Python modules is to install Anaconda. For this Rocky Linux installation we downloaded Anaconda version 2023.03 with: 
curl -O https://repo.anaconda.com/archive/Anaconda3-2023.03-1-Linux-x86_64.sh
Currently, with a later Anaconda version (2023.07 with Python 3.11) we could not build the GIPSY Python module whatever version of Cython you install (see next paragraph).

One important package is not installed automatically and that is Cython.
If you install it with conda, you get probably version 3.0 which has some bugs
which prevents you to build the pygipsy module. To force a lower version, we installed it with: 
pip install "cython<3"


Wayland versus X11

A minimal installation seems to set the defaults to Wayland (a modern replacement for X11, see https://wayland.freedesktop.org/
There are a number of issues at the time of writing this document (Sep 18, 2023) with Wayland. So we upgraded the RL9 installation to Workstation with: 
sudo dnf group install Workstation
A user who enters a username at login, is able, through the little maintenance wheel, to select a desktop that is based on (Xorg/X11). After entering the password, a desktop will appear which is suitable to run all GIPSY graphical interfaces.


Additional: ffmpeg

ffmpeg is necessary to make videos in VISIONS. Plain installation with dnf (as in sudo dnf install ffmpeg) does currently not work for Rocky Linux 9 (15-09-2023)
So follow the instructions on:

https://computingforgeeks.com/install-use-ffmpeg-on-rocky-alma-9/


Missing fonts

If your GIPSY task are complaining about missing fonts, then install them with: 
sudo dnf install xorg-x11-fonts-misc
sudo dnf install xorg-x11-fonts-ISO8859*


MESA-LOADER problems

On virtual machines, when you start applications that use QT, you get warnings about missing libraries. 
MESA-LOADER: failed to open swrast (search paths .......)
libGL error: failed to load driver: swrast
This has to do with the fact that Anaconda uses different versions of libraries also found on the system.
The trick to prevent these warnings is to set:

in .bashrc for bash: export LD_PRELOAD=/usr/lib64/libstdc++.so.6.0.31
in .cshrc for tcsh: setenv LD_PRELOAD "/usr/lib64/libstdc++.so.6.0.31"

The version number could be different for your system of course.


A GIPSY configuration script

A GIPSY configuration script 'setgipsy.sh' that sets the environment could be: 
export gip_root='/home/someuser/GIPSY'
source $gip_root/sys/gipenv.sh
export LD_PRELOAD=/usr/lib64/libstdc++.so.6.0.31
which you activate on the command line with 
source setgipsy.sh
Sep 15, 2023
GIPSY