/usr/lib/python3/dist-packages/pyvisa/ctwrapper/cthelper.py is in python3-pyvisa 1.8-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 | # -*- coding: utf-8 -*-
"""
pyvisa.ctwrapper._ct
~~~~~~~~~~~~~~~~~~~~
Cross platform helper of ctypes.
This file is part of PyVISA.
:copyright: 2014 by PyVISA Authors, see AUTHORS for more details.
:license: MIT, see LICENSE for more details.
"""
from __future__ import division, unicode_literals, print_function, absolute_import
# ctypes and os shouldn't be re-exported.
import os as _os
import sys as _sys
import ctypes as _ctypes
PYTHON3 = _sys.version_info >= (3, 0)
if _os.name == 'nt':
FUNCTYPE, Library = _ctypes.WINFUNCTYPE, _ctypes.WinDLL
else:
FUNCTYPE, Library = _ctypes.CFUNCTYPE, _ctypes.CDLL
# On Linux, find Library returns the name not the path.
# This excerpt provides a modified find_library.
# noinspection PyUnresolvedReferences
if _os.name == "posix" and _sys.platform.startswith('linux'):
# Andreas Degert's find functions, using gcc, /sbin/ldconfig, objdump
def define_find_libary():
import re
import tempfile
import errno
def _findlib_gcc(name):
expr = r'[^\(\)\s]*lib%s\.[^\(\)\s]*' % re.escape(name)
fdout, ccout = tempfile.mkstemp()
_os.close(fdout)
cmd = 'if type gcc >/dev/null 2>&1; then CC=gcc; else CC=cc; fi;' \
'$CC -Wl,-t -o ' + ccout + ' 2>&1 -l' + name
trace = ''
try:
f = _os.popen(cmd)
trace = f.read()
f.close()
finally:
try:
_os.unlink(ccout)
except OSError as e:
if e.errno != errno.ENOENT:
raise
res = re.search(expr, trace)
if not res:
return None
return res.group(0)
def _findlib_ldconfig(name):
# XXX assuming GLIBC's ldconfig (with option -p)
expr = r'/[^\(\)\s]*lib%s\.[^\(\)\s]*' % re.escape(name)
res = re.search(expr,
_os.popen('/sbin/ldconfig -p 2>/dev/null').read())
if not res:
# Hm, this works only for libs needed by the python executable.
cmd = 'ldd %s 2>/dev/null' % _sys.executable
res = re.search(expr, _os.popen(cmd).read())
if not res:
return None
return res.group(0)
def _find_library(name):
path = _findlib_ldconfig(name) or _findlib_gcc(name)
if path:
return _os.path.realpath(path)
return path
return _find_library
find_library = define_find_libary()
else:
from ctypes.util import find_library
|