Re: _AS_DETECT_BETTER_SHELL speedup

[Alexandre Duret-Lutz]

It seems to me that replacing

   (foo) 2>/dev/null

by

   (exec foo) 2>/dev/null

would also replace two forks by one, and it looks a lot less
risky.  

However my understanding is that modern shells already detect
these cases and perform the optimization by themselves.  I know
for sure that Zsh has the machinery for this (along with some
other hairy tricks to limit forks at other places), and, from
what I can observe from the command line, so does Bash.  

IMHO: don't bother and let the shell do its job.
-- 
Alexandre Duret-Lutz