1.5.24: data corruption problem with popen and gzip on a text mounted filesystem
Mon Jul 23 18:02:00 GMT 2007
Eric Blake <ebb9 <at> byu.net> writes:
> Hugh Secker-Walker <hugh <at> merl.com> writes:
> > I'm having trouble getting correct behavior on a third-party OpenSource
> > project that I'm building using Cygwin. The problem involves the
> > writing of corrupt data to a file. The output file is created and
> > written via popen("gzip > outputfile", "wb"). The data is fine if the
> > filesystem is mounted in binary mode. The data is corrupted if the
> > filesystem is mounted in text mode.
> As a workaround, you can force gzip to see stdout in binary mode by
> intermediary pipe, as in popen("gzip | cat > outputfile", "wb").
Thank you. That simple workaround appears to work.
Interestingly, I had tried popen("gzip | dd of=outputfile", "wb") as a
lower-level way to avoid what I guessed was a problem with gzip using
the stdout. The dd attempt didn't work. This failure suggests to me
that dd and gzip experience a similar problem in this popen() context,
a problem that cat somehow avoids.
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Problem reports: http://cygwin.com/problems.html
More information about the Cygwin