Borzenkov Andrey <arvidjaar@newmail.ru> writes:

> Hello Philippe Troin 
> 
> ¿Ý, 28.02.2005 18:29:43 you wrote:
> PT> > -    trap "" SIGTTOU > /dev/null 2>&1 || :
> PT> > +    ( trap "" SIGTTOU > /dev/null 2>&1 ) && trap "" SIGTTOU > /dev/null 2>&1 
> PT> Why?  What does it buy?
> PT> 
> 
> SUS specifies that trap is special builtin so error in "trap" should
> terminate non-interactive shell. On my system (and as Peter hinted
> probably everywhere else) trap SIGTTOU is invalid (trap TTOU is
> valid) so configure exits without any chance to see || :.

Got to love these "special" builtins.  Yet another kind of weird
dehavior.

> To the author of original check - please test if my patch works for
> you as intended and I commit it. Alternative is to change it into
> "trap "" TTOU" that is likely to be more portable.

This will work as intended.  I'd rather use TTOU since it's more
portable.

Patch enclosed.

Phil.

2005-02-28  Philippe Troin  <phil@fifi.org>

	* 20886: configure.ac: Use TTOU with trap rather than SIGTTOU.