ioctl() on socket fd's take 3 seconds on 1.7.7

Corinna Vinschen
Mon Nov 15 16:23:00 GMT 2010

On Nov  9 09:20, Jason Curl wrote:
>   166   65418 [main] ipcheck 5580 ioctl: fd 3, cmd 80087364
> --- Process 5580, exception C0000005 at 610C8C86

Crash in Cygwin, but the address doesn't help much, unfortunately.

> Interestingly enough, the program works. That is, it finds all
> interfaces and returns correct values (except interface names are
> UUIDs instead of something more friendly like "eth0" that existed in
> 1.5.26).

For a reason.  The UUID names are the only officially *unique* interface
names available in Windows.  The ethX names in Cygwin 1.5 were faked,
based on the order in which the interfaces appear in a Windows call.
This order is not guaranteed to stay intact during the uptime of a
machine.  Cygwin also provides an ioctl called SIOCGIFFRNDLYNAM, which
provides the interface name shown in the Windows network adapter
settings window.

> My antivirus has been closed (not simply deactivated) with no change
> in behaviour.
> It will be a little later when I'm able to generate a working test case.

T'would be nice.  Please make it short and simple and, if possible, in
plain C.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

Problem reports:
Unsubscribe info:

More information about the Cygwin mailing list