eryksun added the comment:
Popen calls Windows [CreateProcess][1]. If the Popen "executable" argument
isn't used or if the file from the command line doesn't include a directory
path, then CreateProcess searches for it in the following directories:
1. The directory from which the application loaded.
2. The current directory for the parent process.
* This step is skipped if the parent defines
%NoDefaultCurrentDirectoryInExePath%.
3. The 32-bit Windows system directory.
4. The 16-bit Windows system directory.
5. The Windows directory.
6. The directories that are listed in the PATH
environment variable.
Also note that the PATH searched is that of the *parent* process; the "env"
parameter doesn't affect this.
Call the SearchPath function if you need a custom search for the fully
qualified path.
import ctypes
from ctypes import wintypes
kernel32 = ctypes.WinDLL('kernel32')
kernel32.SearchPathW.argtypes = (
wintypes.LPCWSTR, # _In_opt_ lpPath
wintypes.LPCWSTR, # _In_ lpFileName
wintypes.LPCWSTR, # _In_opt_ lpExtension
wintypes.DWORD, # _In_ nBufferLength
wintypes.LPWSTR, # _Out_ lpBuffer
ctypes.POINTER(wintypes.LPWSTR)) # _Out_opt_ lpFilePart
def search_path(filename, path=None, ext='.exe'):
length, new_length = 0, 260
while new_length > length:
length = new_length
filepath = (ctypes.c_wchar * length)()
new_length = kernel32.SearchPathW(path, filename, ext,
length, filepath, None)
return filepath.value
For example:
>>> search_path('python')
u'C:\\Program Files\\Python27\\python.exe'
>>> import os
>>> search_path('python', os.environ['PATH'])
u''
>>> search_path('more.com', os.environ['PATH'])
u'C:\\Windows\\System32\\more.com'
>>> search_path('more', ext='.com')
u'C:\\Windows\\system32\\more.com'
[1]: https://msdn.microsoft.com/en-us/library/ms682425
----------
nosy: +eryksun
_______________________________________
Python tracker <rep...@bugs.python.org>
<http://bugs.python.org/issue24793>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
