Re: POSIXLY_CORRECT not correctly unset in getopt.m4?

[Eric Blake]

On 09/07/2010 02:09 PM, Bruno Haible wrote:
>    $ env | grep POSIXLY_CORRECT
>    POSIXLY_CORRECT=1
>    $ echo ${POSIXLY_CORRECT+set}
>
> > Any other ideas for portable ways of detecting whether a shell variable
> > is currently local-only or exported?
>
> 'printenv' does not exist on Solaris.
>
> But 'awk' is among the list of portable programs. This should work:
>
>    if test `awk 'BEGIN { print ENVIRON["POSIXLY_CORRECT"] }'<  /dev/null | wc 
> -c` = 1; then
>      : # POSIXLY_CORRECT is not exported
>    else
>      : # POSIXLY_CORRECT is exported
>    fi

Thanks for the tip!  With that, I can come up with a more concise awk 
script, given that hint, and awk is already on the GCS approved list. 
(Still, it would be nice to add env.)  POSIX guarantees that awk 
supplies ENVIRON; are we assuming that this is reasonable portable to 
all the old-and-crusty vendor implementations out there, since the 
autoconf manual doesn't state otherwise?

--
Eric Blake   address@hidden    +1-801-349-2682
Libvirt virtualization library http://libvirt.org