#!/usr/bin/env python
#############################################################################
##
# This file is part of Taurus
##
# http://taurus-scada.org
##
# Copyright 2011 CELLS / ALBA Synchrotron, Bellaterra, Spain
##
# Taurus is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
##
# Taurus is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
##
# You should have received a copy of the GNU Lesser General Public License
# along with Taurus. If not, see .
##
#############################################################################
"""Find path of executable specified by filename"""
__all__ = ["whichfile"]
__docformat__ = "restructuredtext"
import os
def whichfile(filename, exts=None):
'''Find path of executable specified by filename.
It Takes into consideration
the PATHEXT variable (found in MS Windows systems) to try also executable
names extended with executable extensions.
Example::
# on a debian machine with taurus installed in the default path:
whichfile('taurus') --> '/usr/bin/taurus'
# or, on a winXP machine:
whichfile('command') --> 'C:\\WINDOWS\\system32\\command.COM'
:param filename: (str) executable name.
:param exts: (list) a list of valid executable extensions.
If None given, the PATHEXT environmental variable is used
if available.
:return: (str) absolute path to the executable in the file system
'''
path = os.getenv('PATH', '').split(os.path.pathsep)
if exts is None:
exts = os.getenv('PATHEXT', '').split(os.path.pathsep)
if '' not in exts:
exts.insert(0, '')
for p in path:
p = os.path.join(p, filename)
for e in exts:
pext = p + e
if os.access(pext, os.X_OK):
return pext
return None