Created attachment 1665 [details]
Patch to wrap call to termios.TIOCGWINSZ in a try/except block

On an Irix 6.5.24 system, TIOCGWINSZ is not available. This means that any usage of the "hg" tool that looks up the terminal size (e.g. "hg help") will fail with an AttributeError.

A simple work-around is just to wrap this block in mercurial/posix.py with a try/except (attached patch) so that it ends up using the default 80 characters width. 

There may be a better way to get this information from an Irix system instead of falling back to 80 characters, but I'm not aware of the best way to go about this. 

I appreciate Irix is not exactly a current platform, but aside from the TIOCGWINSZ issue, Mercurial works very well on it. The patch would probably also help other older/obscure Unix-like systems and seems to have a minimal impact on anything else.

Thanks,

-Mark