To get the latest GDL you really need to compile from source.

• https://gnudatalanguage.github.io/gdl.wiki/GDL-on-Linux.html

1. Grab the source
   1. Choice 1) git repository of current

      mkdir ~/src
      cd src
      git clone https://github.com/gnudatalanguage/gdl

   2. Choice 2) grab a tar ball from https://github.com/gnudatalanguage/gdl/releases

      mkdir ~/down
      cd ~/down
      wget https://github.com/gnudatalanguage/gdl/archive/refs/tags/v1.0.1.tar.gz
      mkdir ~/src
      cd src
      tar -zxvf ~/down/v1.0.1.tar.gz
      ln -s gdl-1.0.1 gdl

2. Using cmake to compile we need some extra packages

   sudo apt install build-essential cmake	
   sudo apt install libncurses-dev libreadline-dev zlib1g-dev libpng-dev libgsl-dev libwxgtk3.0-gtk3-dev libplplot-dev libmagick++-dev libgraphicsmagick++1-dev libgeotiff-dev libnetcdf-dev libfftw3-dev python-dev libudunits2-dev libeccodes-dev libglpk-dev libhdf4-alt-dev python-numpy libeigen3-dev

3. Create a build directory and let's make this thing

   cd ~/src/gdl
   mkdir build
   cd build
   cmake -DQHULL=OFF -DCMAKE_BUILD_TYPE=Release ..
   CPUS=$(grep -c processor /proc/cpuinfo)
   make -j $CPUS # (N depending the number of cores you have)
   make test

4. Install

   sudo make install

export LM_LICENSE_FILE="$HOME/idl/license.dat"

export IDL_PATH="<IDL_DEFAULT>"
export IDL_PATH="$IDL_PATH:$HOME/idl/lvis_current"
export IDL_PATH="$IDL_PATH:$HOME/idl/lvis_utils"
export IDL_PATH="$IDL_PATH:$HOME/idl/lvisf"
export IDL_PATH="$IDL_PATH:$HOME/idl/lvis_classic_2019"
export IDL_PATH="$IDL_PATH:$HOME/idl/lvis21"
export IDL_PATH="$IDL_PATH:$HOME/idl/lvis"
export IDL_PATH="$IDL_PATH:$HOME/idl/hdl"
export IDL_PATH="$IDL_PATH:$HOME/idl/local"