pari-gp in trixie-backports: please update Unix install documentation

["stes@telenet.be" <stes@telenet.be>]

Hello,

I installed Debian 13.4 (Trixie) on an ASUS (AsusTek) machine, a physical computer i.e., an ASUS PC, with an AMD Ryzen 5 4500 cpu and Nvidia GeForce GT730 graphics card to test PARI/GP as announced.

The installation of Debian Linux went fine (Linux kernel 6.12.86+deb13-amd64).

When I install pari-gp using 'apt' I get PARI 2.17.2-1 from the Debian trixie repository.

I installed using the command:

 apt install --no-install-recommends pari-gp

because I was afraid that the recommended texlive packages (TeX for pari-doc) might otherwise be installed if I install pari-gp + all of the suggested or recommended dependencies; I just want to install the pari-gp package by itself which why I use the --no-install-recommends switch (I am not sure whether the PARI documentation addresses this).  I understand that TeX will be required for documentation or other functionality in PARI (so whatever requires texlive or TeX will not work).

Anyway the install did NOT provide PARI 2.17.3; it provided PARI 2.17.2-1 instead.

For PARI 2.17.3 it seems one has to add an additional trixie-backports apt source.

cat /etc/apt/sources.list.d/debian-backports.sources 
# Modernized from /etc/apt/sources.list
Types: deb deb-src
URIs: http://deb.debian.org/debian/
Suites: trixie-backports
Components: main 
Enabled: yes
Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg

Only after running 'apt update' for that entry for APT which enables the supplementary 'trixie-backports' repository, then the install

  apt install -t trixie-backports --no-install-recommends pari-gp

installs version 2.17.3 from the trixie-backports repo that was added to the Debian system.

$ gp
Reading GPRC: /etc/gprc
GPRC Done.

                  GP/PARI CALCULATOR Version 2.17.3 (released)
          amd64 running linux (x86-64/GMP-6.3.0 kernel) 64-bit version
          compiled: May  7 2026, gcc version 14.2.0 (Debian 14.2.0-19)
                   threading engine: pthread, nbthreads = 12
                 (readline v8.2 enabled, extended help enabled)

                     Copyright (C) 2000-2024 The PARI Group

The command 

  apt info -a pari-gp

shows pari-gp

Version: 2.17.3-1~bpo13+1
Maintainer: Bill Allombert <ballombe@debian.org>
APT-Manual-Installed: yes
APT-Sources: http://deb.debian.org/debian trixie-backports/main amd64 Packages

Version: 2.17.2-1
Maintainer: Bill Allombert <ballombe@debian.org>
APT-Sources: http://deb.debian.org/debian trixie/main amd64 Packages

so version 2.17.3 is installed and 2.17.2 is available but not installed.

Would it please be possible to provide some documentation in the PARI FAQ

https://pari.math.u-bordeaux.fr/faq.html

or 

install guide for Unix : https://pari.math.u-bordeaux.fr/pub/pari/manuals/2.17.2/INSTALL.pdf

The install guide discusses compiling PARI but not installing it from apt or trixie-backports etc.

The FAQ has a system specific part and indicates that it is possible to install PARI using "apt install pari-gp" but it does not discuss adding trixie-backports or using the --no-install-recommends switch.

Also are there any plans to provide PARI 2.17.3 for bookworm-backports ?? for Debian 12.13 "bookworm"
https://www.debian.org/News/2026/2026011002

Thanks,
David