Python reload shared library test script

reloadlib.py

#!/usr/bin/env python
#coding: utf-8

import os
import sys
import ctypes

def is_loaded(lib):
    libp = os.path.abspath(lib)
    ret = os.system("lsof -p %d | grep %s > /dev/null" % (os.getpid(), libp))
    return (ret == 0)

def reload_lib(lib):
    handle = lib._handle
    name = lib._name
    del lib
    while is_loaded(name):   
        libdl = ctypes.CDLL("libdl.so")
        libdl.dlclose(handle)
    return ctypes.cdll.LoadLibrary(name)

def main():
    libpath = sys.argv[1]
    lib = ctypes.cdll.LoadLibrary(libpath)
    lib.process()
    raw_input("Rebuilding library....., When you are done, press [ENTER]:")
    lib = reload_lib(lib)
    lib.process()
    print 'DONE'


if __name__ == '__main__':
    main()