how to force pipes into binary mode?

Richard Y. Kim
Sat Apr 18 19:53:00 GMT 1998

>>>>> "Frank" == Frank Baumgart <> writes:

    Frank> So, how do I force my pipes which have been created with
    Frank> pipe() to work in binary mode?


This includes the source for _bash_.
In the bash subdirectory, find the file execute_cmd.c,
In this file, search for the definition of do_piping().
You will see 3 instances of 

  #ifdef __CYGWIN32__
        setmode (0, O_TEXT);

in this function. I believe taking out all three sets of code reverts
_bash_ back to the "correct" setting.  Please correct me if I'm wrong.

I want to thank Larry Hall <> for pointing out where to
find above code when I had the same question as Frank.

    Frank> Or better: are there any patches or even cygwin32.dll
    Frank> available working in binary mode generally? (pipes doing
    Frank> text-mode translation is so stupid!)

I could not agree more based on my personal experience. I tried out
gnu-win32 about two years ago. I dropped it right away, because of
problems which I now think were due to text mode pipes. I did not have
the time nor the incentive to figure out what was going on then. I
gave gnu-win32 another shot about a year ago. I dropped it again after
couple of days due to similar problems. This is my third time
around. This time, I spent more time. With the help of people on
gnu-win32 mailing list, I now understand what I need to do to use

I hope that Cygnus people take out the code they put in to force text
mode pipe in _bash_ in the next release of gnu-win32.

Richard Y. Kim

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