chap2.txt

  
  2 Installation
  
  
  2.1 Installation and system requirements
  
  Both SCSCP client and server for GAP work in Linux, OS X and Windows.
  
  To  use the SCSCP package it is necessary to install recent versions of GAP4
  packages IO [Neu], GAPDoc [LN] and OpenMath [CKS].
  
  The  SCSCP  package is distributed in standard formats (tar.gz, tar.bz2) and
  can  be  obtained from https://gap-packages.github.io/scscp/ or from the GAP
  web  site  (the  latter also offers zoo- and win.zip-archives. To unpack the
  zoo-archive  the program unzoo is needed, which can be obtained from the GAP
  homepage http://www.gap-system.org/ (see section `Distribution'). To install
  SCSCP  package, put its zoo-archive into the pkg subdirectory of your GAP4.4
  installation  and  enter  the  command  unzoo  -x  scscp-X.X.X.zoo, then the
  subdirectory scscp (containing subdirectories doc, lib etc.) will be created
  in  the  pkg  subdirectory.  Installation  using  other  archive  formats is
  performed in a similar way.
  
  When  there  are  no  access  rights  to  the root directory of the main GAP
  installation,  it  is  also  possible to install the package outside the GAP
  main directory by unpacking it inside a directory MYGAPDIR/pkg. Then to load
  the package GAP should be started with -l ";MYGAPDIR" option.
  
  
  2.2 Configuration files
  
  There  are  four files in the package which may need to be modified to setup
  and  customise  the  package.  The  first  three  files are related with the
  server's functionality:
  
      scscp/config.g specifies:
  
            default InfoLevel for the InfoSCSCP (9.2-1) class;
  
            default  SCSCP server name and port to be used by RunSCSCPserver
              (5.2-1)  if  GAP  is  started  with the scscp/example/myserver.g
              file;
  
            whether  the  server  accepts  calls  to  procedures  which  are
              standard  OpenMath  symbols, or only procedures installed in the
              transient    content   dictionary   (see   InstallSCSCPprocedure
              (5.1-1));
  
            service   description   to   be   returned   to  the  client  by
              GetServiceDescription (5.3-1).
  
      scscp/gapd.sh is the script to start the GAP SCSCP server as a daemon.
        To  use  it,  adjust  the  local  call  of GAP and, if necessary, call
        options  (for  example, memory usage, startup from the workspace etc.)
        and the location of the root directory of the SCSCP package in section
        1 of this script.
  
      scscp/example/myserver.g  is  an  example  of the server configuration
        file  which  loads  all  necessary  packages,  reads  all needed code,
        installs  all  procedures  which  will  be  exposed  to the client and
        finally starts the SCSCP server (see Chapter 5).
  
  The  fourth  file  is  related  with the client's functionality for parallel
  computations:
  
      The  file  scscp/configpar.g  assigns the global variable SCSCPservers
        which specifies a list of hosts and ports to search for SCSCP services
        (which  may  be  not  only  represented  by  GAP services, but also by
        another  SCSCP-compliant  systems).  It  will  be used to run parallel
        computations with the SCSCP package (see Chapter 8).
  
  See comments in these configuration files for further details and examples.