NAME

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

SYNOPSIS

       pcp python [SCRIPT [ARG] ...]

DESCRIPTION

       pcp-python  has  been  replaced  by  pmpython(1) which is preferred, however pcp-python is
       still installed to provided backwards compatibility.

       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

       PCPIntro(1) and pcp(1).