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win32+popen4

Thomas Heller theller at python.net
Fri Mar 1 10:33:10 EST 2002 
"Robin Becker" <robin at jessikat.fsnet.co.uk> wrote in message news:PtFyMdAeY5f8EwjI at jessikat.demon.co.uk...
> after investigation it seems that module nt is using
>         cmd.exe /c string
>
> to run programs and I can't find any way to quote things in the string.
> A typically rubbish M$-ism.
> --
> Robin Becker

On win2k it seems to be even documented (for the first time?):

C:\sf\python>type "\Program Files\test.py"
import sys
print sys.argv
C:\sf\python>cmd /c ""\Program Files\test.py" "1 2 3" 4 5 "6""
['C:\\Program Files\\test.py', '1 2 3', '4', '5', '6']

and here are the rules:

C:\sf\python>cmd /?
Starts a new instance of the Windows 2000 command interpreter

CMD [/A | /U] [/Q] [/D] [/E:ON | /E:OFF] [/F:ON | /F:OFF] [/V:ON | /V:OFF]
    [[/S] [/C | /K] string]

/C      Carries out the command specified by string and then terminates
/K      Carries out the command specified by string but remains
/S      Modifies the treatment of string after /C or /K (see below)
/Q      Turns echo off
/D      Disable execution of AutoRun commands from registry (see below)
/A      Causes the output of internal commands to a pipe or file to be ANSI
/U      Causes the output of internal commands to a pipe or file to be
        Unicode
/T:fg   Sets the foreground/background colors (see COLOR /? for more info)
/E:ON   Enable command extensions (see below)
/E:OFF  Disable command extensions (see below)
/F:ON   Enable file and directory name completion characters (see below)
/F:OFF  Disable file and directory name completion characters (see below)
/V:ON   Enable delayed environment variable expansion using c as the
        delimiter. For example, /V:ON would allow !var! to expand the
        variable var at execution time.  The var syntax expands variables
        at input time, which is quite a different thing when inside of a FOR
        loop.
/V:OFF  Disable delayed environment expansion.

Note that multiple commands separated by the command separator '&&'
are accepted for string if surrounded by quotes.  Also, for compatibility
reasons, /X is the same as /E:ON, /Y is the same as /E:OFF and /R is the
same as /C.  Any other switches are ignored.

If /C or /K is specified, then the remainder of the command line after
the switch is processed as a command line, where the following logic is
used to process quote (") characters:

    1.  If all of the following conditions are met, then quote characters
        on the command line are preserved:

        - no /S switch
        - exactly two quote characters
        - no special characters between the two quote characters,
          where special is one of: &<>()@^|
        - there are one or more whitespace characters between the
          the two quote characters
        - the string between the two quote characters is the name
          of an executable file.

    2.  Otherwise, old behavior is to see if the first character is
        a quote character and if so, strip the leading character and
        remove the last quote character on the command line, preserving
        any text after the last quote character.
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