NAME

       pcp-python - run a python script using a preferred python variant

SYNOPSIS

       pcp python [SCRIPT [ARG]...]

DESCRIPTION

       pcp-python provides a way to run python scripts using a customisable python binary, rather
       than embedding any particular version of python into each script.

       This can be useful as it allows version-independent python code to be run  anywhere.   All
       python  modules  shipped  with PCP support versions 2.6 and later (in the python2 series),
       and 3.3 and later (in the python3 release series).

       Due to python monitoring and collecting  scripts  being  relatively  simple  in  PCP  (not
       requiring  new  modules, language features, etc), it has been possible to ensure they work
       for all of the above python versions.  Thus, it is common for PCP python scripts to use  a
       "shebang" line that invokes pcp-python as follows:

          #!/usr/bin/pcp python

       This  allows  the  custom  setting  to be injected instead of a hard-coded python version,
       while still allowing the user to override the python version as follows:

          $ PCP_PYTHON_PROG=python3 /usr/bin/pcp python --version
          Python 3.3.2
          $ PCP_PYTHON_PROG=python2 /usr/bin/pcp python --version
          Python 2.7.5

       This is convenient for shipping identical scripts on multiple platforms, and  for  testing
       different python versions with the one script (e.g. in the case where multiple versions of
       python are installed, PCP_PYTHON_PROG can be set in the local environment to override  the
       global setting).

       By  default,  the  value  of PCP_PYTHON_PROG from /etc/pcp.conf will be used.  The default
       value of this configuration parameter is set depending on some heuristics about the target
       build platform.  These heuristics favour the use of python3 in all recent releases of PCP,
       for those platforms that support it.

PCP ENVIRONMENT

       Environment variables with the prefix PCP_ are used to parameterize the file and directory
       names used by PCP.  On each installation, the file /etc/pcp.conf contains the local values
       for these variables.  The $PCP_CONF  variable  may  be  used  to  specify  an  alternative
       configuration file, as described in pcp.conf(5).

SEE ALSO

       pcp(1) and PCPIntro(1).