Development for LHC@home

The following lines check for singularity and set the version from CVMFS if there's no local installation.

def check_singularity(sin_binary):
  logger.info("Checking Singularity...")
  (ret,mes)=commands.getstatusoutput("%s --version" % sin_binary)
  if ret!=0:
    if mes.find('not found') != -1:
      logger.info("Singularity is not installed, using version from CVMFS")
    else:
      logger.info("Singularity seems to be installed but not working: %s" % mes)
      logger.info("Will use version from CVMFS")
    sin_binary = '/cvmfs/atlas.cern.ch/repo/containers/sw/singularity/x86_64-el7/current/bin/singularity'
  else:
    logger.info("Singularity is installed, version %s" % mes)
  return sin_binary

You may be aware that on my hosts the check doesn't include "not found" in it's output:

> singularity --version
If 'singularity' is not a typo you can use command-not-found to lookup the package that contains it, like this:
    cnf singularity

Hence the script logs "Singularity seems to be installed but not working" instead of "Singularity is not installed ...".

Another host logs the message in german language which also doesn't include "not found":

singularity: Kommando nicht gefunden.