bazarr/libs/subzero/lib/which.py

44 lines
1.4 KiB
Python

# coding=utf-8
# https://gist.github.com/4368898
# Public domain code by anatoly techtonik <techtonik@gmail.com>
# AKA Linux `which` and Windows `where`
from __future__ import absolute_import
import os
import sys
def find_executable(executable, path=None):
"""Find if 'executable' can be run. Looks for it in 'path'
(string that lists directories separated by 'os.pathsep';
defaults to os.environ['PATH']). Checks for all executable
extensions. Returns full path or None if no command is found.
"""
if path is None:
path = os.environ['PATH']
paths = path.split(os.pathsep)
extlist = ['']
if os.name == 'os2':
(base, ext) = os.path.splitext(executable)
# executable files on OS/2 can have an arbitrary extension, but
# .exe is automatically appended if no dot is present in the name
if not ext:
executable = executable + ".exe"
elif sys.platform == 'win32':
pathext = os.environ['PATHEXT'].lower().split(os.pathsep)
(base, ext) = os.path.splitext(executable)
if ext.lower() not in pathext:
extlist = pathext
for ext in extlist:
execname = executable + ext
if os.path.isfile(execname):
return execname
else:
for p in paths:
f = os.path.join(p, execname)
if os.path.isfile(f):
return f
else:
return None