{lp,cb}Reserved2 under Windows 7 and file descriptors

Daniel Colascione dan.colascione@gmail.com
Sun Sep 12 22:10:00 GMT 2010

On 9/12/10 2:29 PM, Andy Koppe wrote:
> This does appear to work! Proof-of-concept code attached, along with a
> couple of tests. Running in mintty:

Awesome. Thanks for doing this work. I believe the Cygwin developers had
concerns about this change inadvertently breaking some applications.
Have you noticed any unusual behavior?

> Unfortunately it only seems to work for fdev's direct child process
> though. For example, when running cmd.exe through fdev and invoking
> isatty.exe from there, it's all zeroes from isatty() again.

Unfortunately, cmd.exe does not appear to use the C runtime IO library,
and it doesn't pass on inherited file descriptors --- except for the
standard handles via CreateProcess. It's a shame, too, because cmd
understands the syntax for manipulating the first ten file descriptors
in much the same way that a unix shell does.

I think it would work for other families of process though, and it's
still an improvement.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 195 bytes
Desc: OpenPGP digital signature
URL: <http://cygwin.com/pipermail/cygwin/attachments/20100912/3c761d4d/attachment.sig>

More information about the Cygwin mailing list