Eli Zaretskii wrote:
> What problems did you see/envision on other platforms with the
> original patch?

Mainly the hassle of maintaining code with a lot of hard-to-read ifdefs in it. 
It's better if system-specific stuff is kept to a minimum in mainline code. 
Also, this O_PATH stuff is not that high of a priority, as the code works quite 
well in practice without O_PATH. (Also, if Cygwin botched O_PATH on FIFOs 
there's a reasonable chance it botched O_PATH elsewhere too. :-)

How about something like the attached patch instead? It's simpler and should be 
a bit faster on Cygwin than the original patch. I haven't tested it.