set -o posix

[Pavel Roskin]

Hello!

Could anybody please look at "man pdksh" and check whether "set -o posix"
in pdksh will make any difference for Autoconf.

The testsuite passes under pdksh without "set -o posix" just fine, but if
Autoconf relies on some constructs that behave differently it would be
nice to add a test.

The later applies to bash as well. It would be nice to check whether
"set -o posix" in bash has the desired effect.

What exactly does "set -o posix" fix in bash that is relevant to Autoconf?

Regards,
Pavel Roskin