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                         Installation guidelines

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 Table of contents:

    I - ABOUT

    II - DOWNLOAD
      1) Retrieving sources from GILDAS homepage
      2) Retrieving sources from GIT repository
      3) Retrieving documentation from GILDAS homepage

    III - REQUIREMENTS
      1) Material
      2) Needed tools to build executables
      3) Needed tools to build the documentation

    IV - INSTALL UNDER MAC OSX
      1) MacPorts package
      2) Installation from sources
      3) Troubleshooting

    V - INSTALL UNDER LINUX
      1) Dependencies
      2) Compile and install (binaries)
      3) Post-installation (binaries)
      4) Compile and/or install (documentation)
      5) Troubleshooting

    VI - INSTALL UNDER MS WINDOWS

    VII - UNINSTALL
      1) Under Linux
      2) Under MacPorts

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I - ABOUT
----------

  Please contact gildas<at>iram.fr for any question, remark,
  suggestion.

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II - DOWNLOAD
--------------

  1) Retrieving sources from GILDAS homepage:

     Linux/OSX version of GILDAS are distributed only as sources
     because binaries are not portable (due to the many different
     possible combinations of processors, operating system and
     compilers). Tarballs of the GILDAS sources are distributed at the
     address:
       https://www.iram.fr/~gildas/dist/
     You have to pick a tarball named gildas-src-mmmyyv.tar.xz. Some
     hints:
     - VERSION: the basic rule to pick up a release is to download and
       install the latest monthly release available on this
       area. Daily releases are there just as a convenience for beta
       testers. We strongly discourage standard user to get them.
     - LABELLING: the suffix 'a', 'b', 'c' and so on indicates that an
       important bug fix or feature has been added during the month
       and this could not wait for the new release at the beginning of
       next month. Such new releases include only these modifications,
       and not all the on-going developpements. Check the NEWS section
       for details on the augmented release.
     - STABILITY: Developpers usually stabilize (if needed) Gildas
       before each release. Nevertheless, some developments take time
       and in such a case monthly releases may be skipped. From time
       to time some releases are suffixed "beta": this indicates that
       important developments were done and this version is a
       candidate for a stable release. It is "stable as far as we
       know", but not tested enough.
     - REFERENCE VERSION: Finally, the jun22 release (June 2022) is a
       particular version used at the telescopes. If a newer version
       is available, standard users should not install the jun22 one,
       unless they have been told to. There are bug fixes,
       improvements, and features which have been added in the latest
       releases, but which won't be in the jun22 release because they
       do not affect the operations at the telescopes.

  2) Retrieving sources from GIT repository:

     Get the last monthly version from the public GIT repository
       shell-prompt> git clone \
         -b ryy-mmm https://git.iram.fr/gildas/gildas.git gildas-src-mmmyy
     This command creates the sources of GILDAS in a new
     gildas-src-mmmyy directory. The "-b ryy-mmm" switch enable you to
     choose the monthly release you need. Be careful, you here need
     only the 3 first letters of the current month and the last two
     digits of the current year. No letter is required: you will
     automatically end up with the last bug fix of this monthly
     release.
     In practice, if you want to fetch the December 2022 sources, just
     type:
       shell-prompt> git clone \
         -b r22-dec https://git.iram.fr/gildas/gildas.git gildas-src-dec22
     It also possible to update this clone at any moment:
       shell-prompt> cd gildas-src-dec22
       shell-prompt> git pull  # Fetch the last commits in the current branch
     If new monthly versions have been released, you should be able
     to check them out after git pull, e.g.
       shell-prompt> git checkout r23-jan  # Fetch January 2023 release
     Do not forget to completely clean and rebuild GILDAS after an
     update (make distclean && make).

  3) Retrieving documentation from GILDAS homepage:

     Compiled documentation is distributed as tarballs at the address:
       https://www.iram.fr/~gildas/dist/
     You have to pick a tarball named gildas-doc-mmmyy.tar.xz

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III - REQUIREMENTS
-------------------

  1) Material:

     - Building the GILDAS binaries under Linux or Mac OSX requires
       about 300 MB of temporary disk space (compilation) and 100 MB of
       permanent disk space (installation).
     - The gfortran compiler might require up to 5-6 GB of RAM when
       compiling GILDAS sources. At run time, GILDAS executables require
       about 1 MB at startup, but then consume as much memory as data
       created or loaded in memory.

  2) Needed tools to build executables:

     Successful building of GILDAS binaries on a UNIX/Linux/OSX system
     minimally requires:
     - Bourne compatible shell (sh, ksh, bash, etc...) for build purpose
       only. The end-users can then use the GILDAS programs from csh-like or
       Bourne-like shells.
     - NROFF for on-line help building.
     - Perl for automatic interface extraction during compilation process.
     - A C compiler (either GCC or the native C compiler).
     - GNU make:
       The current building system is using the GNU make facility which has
       some some desirable but non-portable features (i.e. including
       makefiles, conditions). This does not seem a strong limitation as it is
       easy to install GNU make for your system. In fact, GNU make is the
       default for linux boxes. For others OS, just try to type gmake instead
       of make: it is probably already installed.
     - A FORTRAN 90/95/2003/2008 compiler:
       Latest GNU Fortran (gfortran >= 9.0) and Intel Fortran Compiler
       (ifort > 11.1) are supported.
     - GTK 2 development tools for graphic and widget support.
     - Python >= 3.6 and its array module Numpy if you plan to use the
       Gildas-Python binding, including the Weeds package in
       CLASS.
     - CFITSIO if you plan to use MRTCAL or CUBE.

  3) Needed tools to build the documentation:

     Successful building of PDF/HTML documentation minimally requires
     recent versions of:
     - ps2epsi
     - epstopdf
     - latex (version 2e with makeidx, graphicx and html package)
     - latex2html
     - pdflatex
     For your convenience, we distribute compiled PDF/HTML
     documentation in case you do not have those tools. See the
     distribution section of the GILDAS web page:
     https://www.iram.fr/~gildas/dist/

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IV - INSTALL UNDER MAC OSX
---------------------------

  Gildas and its dependencies can be installed with the MacPorts
  package manager (www.macports.org).

  0) Prerequisites:

     Both installation methods 1 and 2 below require the installation
     of:
     - Xcode, needed by MacPorts. Get it from
       https://developer.apple.com/xcode/ with an Apple identifier
       (more than 1 GB to be downloaded from the app store). See
       e.g. the Xcode installation guidelines suited for MacPorts at
       www.macports.org/install.php
     - Xquartz, needed for Gildas plots (www.xquartz.org). XQuartz is
       successfully installed if the command "xclock" is available and
       opens a clock in a small graphical window. If not, start
       Xquartz from Applications > Utilities > XQuartz.
     - MacPorts, a package manager, is needed retrieve and install
       transparently Gildas and its dependencies. Follow MacPorts
       installation guidelines at www.macports.org/install.php
       MacPorts is successfully installed when e.g. the command "port
       help" is available.

  1) MacPorts package:

     Gildas is available as a standard package in the MacPorts
     distribution. Unless you are an advanced user (see below:
     Installation from sources), this is the recommended way to
     install Gildas under Mac OS. Once MacPorts and XQuartz are
     installed, Gildas installation is straightforward. Type:
        sudo port install gildas
     The parallelization is enabled by default. The Gildas programs
     are ready to use right after (type e.g. "greg" in a terminal
     prompt). Usually the package is updated a few days after a source
     release (every month), so that the latest enhancements or bug
     fixes in Gildas are quickly available to Mac users. Updating to
     the newest release is done with the command:
        sudo port upgrade gildas
     You might need to update MacPorts itself first:
        sudo port selfupdate

  2) Installation from sources:

     As an alternate solution, it is possible to compile Gildas by
     yourself. You have to use MacPorts to install first the Gildas
     dependencies.
     - Installing the dependencies:
          shell> sudo port install gcc13
          shell> sudo port select gcc # show available arguments
          shell> sudo port select gcc mp-gcc13  # Choose the desired one
          shell> sudo port install gtk2
          shell> sudo port install pkgconfig
	  shell> sudo port install groff
     - CFITSIO is needed for CUBE (position-position-velocity cube
       analysis) and MRTCAL (the 30m calibration software). Have a
       look at:
          shell> sudo port variants cfitsio
       Then install the correct "variant" e.g.
          shell> sudo port install cfitsio +gcc14
     - Finally you can follow the standard Linux steps to compile
       Gildas from the sources (see below).

  3) Troubleshooting:

     - If you have problem with rsync when running "sudo port
       selfupdate", you can modify the file
       /opt/local/etc/macports/sources.conf by replacing the line:
          rsync://rsync.macports.org/release/ports/ [default]
       with:
          #rsync://rsync.macports.org/release/ports/ [default]
          https://www.macports.org/files/ports.tar.gz [default]
       and run "sudo port sync" instead of "sudo port selfupdate".
          shell> sudo port install gcc13
          shell> sudo port install gtk2
          shell> sudo port select gcc # show available arguments
          shell> sudo port select gcc mp-gcc13
     - Mac OSX 10.7 (Lion) users: if possible, try to avoid to install
       Python from MacPorts. If installed, you might experience this
       bug when the Gildas-Python binding is started at runtime. If
       so, you should configure your system to prefer the Apple-Python
       rather than the MacPorts-Python:
          shell> port select python python27-apple
       However, note that this may break other Python-related
       applications installed with MacPorts.
     - If the Gildas installation fails and the log file shows the
       following error:
         :info:build FATAL:/opt/local/bin/../libexec/as/x86_64/as:
         I don't understand 'm' flag!
       This problem is described here:
         https://trac.macports.org/ticket/56919
       In short, the assembler program ('as') which is used is not the
       correct one. Type
         sudo port install cctools +xcode
       to switch to the correct version. Then you can resume the
       Gildas installation.
     - If the Gildas installation fails and the log file shows the
       following error:
         :info:build ld: unexpected token: !tapi-tbd-v3 file
         '/System/Library/Frameworks//CoreFoundation.framework/CoreFoundation.tbd'
         for architecture x86_64
       This problem is described here:
         http://mac-os-forge.2317878.n4.nabble.com/linker-errors-ld-unexpected-token-tapi-tbd-v3-file-td363061.html#a363073
       In short, you should type:
         sudo port install ld64 +ld64_xcode
       Then you should retry Gildas installation. You should clean the
       previous attempt first:
         sudo port clean gildas
       Then proceed:
         sudo port install gildas + any option if needed
     - If the program won't open any graphical window and shows this
       warning instead:
         Gtk-WARNING **: xx:xx:xx.xxx: cannot open display
       check that XQuartz server is installed and running (see
       Prerequisites section above).
     - If you observe this message when opening a Gildas program,
       please see the same TROUBLESHOOTING section for Linux:
        Gtk-WARNING **: Locale not supported by C library.
                        Using the fallback 'C' locale.
     - GREG hardcopies to PDF are ensured through system utilities ps2pdf
       and epstopdf. They can be installed thanks to the following ports:
          shell> sudo port install texlive-basic      # provides ps2pdf
          shell> sudo port install texlive-fontutils  # provides epstopdf

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V - INSTALL UNDER LINUX
------------------------

  1) Dependencies:

     In addition to the standard developper tools (make, gcc, nroff,
     etc), the following dependencies must be installed. Root
     priviledges are required here.

     - Fedora 42 (or redhat-like distributions):
        Required:    dnf install gcc-gfortran gcc-c++ gtk2-devel
        Recommended: dnf install python-devel python-setuptools numpy \
                                 libpng-devel cfitsio-devel openssl-devel \
                                 texlive-epstopdf
        Optional:    dnf install fftw-devel
        Install:     follow installation steps at paragraph 2

     - Ubuntu 24.04 (or debian-like distributions):
        Required:    sudo apt install gfortran g++ libgtk2.0-dev
        Recommended: sudo apt install python3-dev python3-numpy python3-setuptools \
                                      libcfitsio-dev libssl-dev texlive-font-utils
                     If you choose to install the package python-is-python3 for
                     your convenience, you have to install python-dev-is-python3
                     for consistency.
        Optional:    sudo apt install libfftw3-dev
        Install:     follow installation steps at paragraph 2

  2) Compile and install (binaries):

     Building the binaries should just need the following sequence of
     commands. Gildas itself does not need root priviledges for
     installation and execution: it can be unzipped anywhere and
     installed by any user for its own needs.
        shell-prompt> unxz gildas-src-mmmyya.tar.xz
        shell-prompt> tar -xf gildas-src-mmmyya.tar
     or even simpler, let tar uncompress the archive by itself (automatic
     detection from the file extension):
        shell-prompt> tar -xf gildas-src-mmmyya.tar.xz
        shell-prompt> cd gildas-src-mmmyya
     At this stage, if you are not under a sh-compatible shell, you
     have to switch to e.g. bash. Then load the compilation
     environment:
        shell-prompt> source admin/gildas-env.sh
     You can optionally add the compiler to be used with the option
     "-c" (e.g. source admin/gildas-env.sh -c gfortran). You can also
     enable the parallelization with OpenMP with the following switch:
        shell-prompt> source admin/gildas-env.sh -o openmp

     This is useful in particular in Mapping. Read carefully the
     messages and warnings returned by the command. If everything seems
     correct, then compile and install Gildas:
        shell-prompt> make
        shell-prompt> make install
     Finally, follow the instructions at the end of the make install
     process. Installation is successful if you can start the programs
     'greg' or 'class' from a new terminal.

  3) Post-installation (binaries):

     After the installation is successful, you can optionally remove
     the sources and compilation directory (gildas-src-mmmyy). This is
     useful only to save disk space. On the other hand, this means
     that in case of update (e.g. for GIT-based downloads) you will
     have to recompile everything again from scratch.

  4) Compile and/or install (documentation):

     - From the tarball archive (easiest):
          shell-prompt> mv gildas-doc-mmmyya.tar.xz gildas-exe-mmmyya/
          shell-prompt> cd gildas-exe-mmmyya/
          shell-prompt> tar -xf gildas-doc-mmmyya.tar.xz
     - Directly from the sources:
       Compilation of documentation is not done by default when
       compiling executables because: i) it requires special tools
       (see requirements) and ii) it takes time.
       To compile and install the PDF documentation, type:
          shell-prompt> make doc
          shell-prompt> make install-doc
       To compile and install the HTML documentation, please type:
          shell-prompt> make html
          shell-prompt> make install-html

  5) Troubleshooting:

     - This message can be displayed when starting a Gildas program:
        Gtk-WARNING **: Locale not supported by C library.
                        Using the fallback 'C' locale
       This is not a GILDAS issue. This means that your locale
       settings (type "locale" in a terminal) indicate one or more
       locales that are not installed on your system (type "locale -a"
       in a terminal for the full list). You should fix your
       environment variables in order to use an installed locale
       (e.g. export LANG=en_US.utf8, beware this may change your
       programs behavior regarding language), or install the missing
       locale(s).
     - Conflict with Anaconda: when installed from the downloadable
       installer, Anaconda comes with a lot of development tools and
       libraries which override the default system ones, but not in a
       consistent way. This is proved to break software compilation and/or
       execution (Gildas and others). For example:
         astro: /home/user/anaconda/lib/libstdc++.so.6: version 
                `GLIBCXX_3.4.21' not found (required by /home/user/
                gildas-exe-jan17a/x86_64-ubuntu16.04-gfortran/lib/libatm.so)
       This happens because Anaconda gives precedence to its own binaries
       and include files (duplicate but different versions of system ones)
       in the user's environment. There are several ways out of this issue:
         a) Install Anaconda from your OS repositories (instead of custom
            installation in the user account). This way, there should be
            a correct integration of Anaconda within the OS.
         b) Keep Anaconda in the user account, but "hide" it during Gildas
            installation and execution. In other words, you have to ensure
            that there is no reference to Anaconda installation paths in
            the environment variables $PATH and $LD_LIBRARY_PATH. You most
            likely have to edit your ~/.bashrc. Once this is done
            recompile, install, and try executing Gildas. If it runs fine,
            a permanent solution could be to use a shell function which
            loads Anaconda environment only when needed, e.g.
              function anaconda() {
                  export PATH=...
                  export LD_LIBRARY_PATH=...
                  anaconda
              }
         c) The next time you install Anaconda, you should answer "No" to
            the question: "Do you wish the installer to prepend the
            Anaconda<2 or 3>install location to PATH...?". Then use a
            function like the above example to get it working. Reference:
            https://docs.anaconda.com/anaconda/user-guide/faq/#distribution-faq-linux-path

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VI - INSTALL UNDER MS WINDOWS
------------------------------

  MS Windows binaries are not available. If you need to run GILDAS
  under a MS Windows computer, you can install a Linux virtual machine
  and follow the installation instructions as explained in the
  previous section.

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VII - UNINSTALL
---------------

  1) Under Linux

     - Except if you want to save disk space, you have no need to
       uninstall any previous Gildas installation. Each version goes
       into its own 'gildas-src-XXX' and 'gildas-exe-XXX'
       directories. The default version used is ruled by the
       environment variable $GAG_ROOT_DIR that is set in user's
       ~/.bash_profile. You can modify it as you want to point to the
       desired version.
     - Remember to start a new terminal each time you modify your
       ~/.bash_profile .
     - For a complete uninstall of Gildas, just remove the directories
       'gildas-src-XXX' and 'gildas-exe-XXX', and suppress the lines
       related to Gildas in your ~/.bash_profile

  2) Under MacPorts

     - MacPorts keeps older Gildas versions when you install a new
       one. At some point you might want to clean all the useless
       versions. You can check for all installed version with
         sudo port installed gildas
       You will see a list of versions with a @ name, e.g.
         gildas @201808b_0+gcc7
         gildas @201808b_0+gcc7+openmp
         gildas @201809a_0+gcc7+openmp (active)
       Uninstalling a single version can be done with e.g.
         sudo port uninstall gildas @201808b_0+gcc7
       Uninstalling several versions can be done with
         sudo port uninstall gildas
       Answer at the prompt which versions are to be uninstalled.
     - If you wish to completely uninstall MacPorts and Gildas, check
       here for the MacPorts recommendations:
         https://guide.macports.org/chunked/installing.macports.uninstalling.html

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