oracular (1) pcp-python.1.gz

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       pcp-python  has been replaced by pmpython(1) which is preferred, however pcp-python is still installed to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