win32process.CreateProcess inherit handles not working ?

[Chui Tey]

Hi,

I've been trying to get this going for a while and I'd appreciate it
if
someone can point out what's wrong with the following test? It works
fine on Win98 but fails on NT and W2K. I am using Python 2.1

# test.py
#

def setup():
    open("slave.py","w").write("""
import sys
while 1:
    line = sys.stdin.readline()
    if not line: break
    sys.stdout.write("read: %s" % line)
""")
    open("slavein.txt","w").write("""
    The
    Quick
    Brown
    Fox
""")

def test():
    "Does the equivalent of C:\\python21\\python.exe slave.py <
slavein.txt > slaveout.txt"
    _CreateProcess( \
    "C:\\python21\\pythonw.exe", # app
    ['slave.py'],               # args
    'slavein.txt',              # input file
    'slaveout.txt')             # output file
    if open('slaveout.txt','r').read() == "":
        print "Error: stdout not redirected!"
    

def _CreateProcess(app, args, filein, fileout):

    """Returns the pid.
       app = executable name
       args = list of arguments
       filein = name of file to redirect to stdin
       fileout = name of file to redirect the stdout to
    """
 
    import win32process
    import win32file
    import pywintypes
    import win32security
    import win32event
    import win32api

    u_filein = pywintypes.Unicode(filein)
    u_fileout = pywintypes.Unicode(fileout)

    SA_proc = win32security.SECURITY_ATTRIBUTES()
    SA_thrd = win32security.SECURITY_ATTRIBUTES()
    SA_proc.bInheritHandle = 1
    SA_thrd.bInheritHandle = 1
    #SA = None

    SI = win32process.GetStartupInfo()
    SI.dwFlags = win32process.STARTF_USESTDHANDLES
    
    hStdInput = win32file.CreateFile(
        u_filein,                   # filename
        win32file.GENERIC_READ,     # mode
        win32file.FILE_SHARE_READ,  # share
        SA_proc,                    # security attributes 
        win32file.OPEN_EXISTING,    # creation disposition
        win32file.FILE_ATTRIBUTE_NORMAL, # flags
        0                           # hTemplate file
    )
    hStdOutput = win32file.CreateFile(
        u_fileout,                  # filename
        win32file.GENERIC_WRITE,    # mode
        win32file.FILE_SHARE_WRITE, # share
        SA_proc,                    # security attributes 
        win32file.CREATE_ALWAYS,    # creation disposition
        win32file.FILE_ATTRIBUTE_NORMAL, # flags
        0                           # hTemplate file
    )
    SI.hStdInput = SI.hStdInput
    SI.hStdOutput = SI.hStdOutput
    SI.hStdError  = SI.hStdOutput

    cmdline = app + " " + " ".join(args)
    hProcess, hThread, pid, threadid =  \
        win32process.CreateProcess( 
        app,                    # lpApplicationName
        cmdline,                # command line
        SA_proc,                # Process security attributes
        SA_thrd,                # Thread security attributes
        1,                      # Inherit handles
        win32process.DETACHED_PROCESS,  #
        None, 
        None, 
        SI)

    win32event.WaitForSingleObject(hProcess, win32event.INFINITE)

    win32file.CloseHandle(hStdInput)
    win32file.CloseHandle(hStdOutput)
    
    return pid

if __name__=="__main__":
    setup()
    test()