Multiple (multiplexed) simultaneous ssh connections - Cygwin bug?

Darren Tucker dtucker at
Sat Sep 9 02:30:00 EST 2006

Darren Tucker wrote:
> You'll have the stdout and stderr descriptors in the select's readset, 
> which for FD_SETSIZE=64 puts the limit at around 30 connections or so 
> (assuming you're not port forwarding or something too).  What did you 
> bump MAX_SESSIONS to?  It might be overrunning the fd_set.

Thinking about it, that's wrong (I was thinking of poll).  Since select 
uses bitmasks it doesn't matter how many are in each of the readset and 
writeset so the limit would be around 20 concurrent.

Darren Tucker (dtucker at
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     Good judgement comes with experience. Unfortunately, the experience
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