Re: Current trunk fails to build on MS-Windows

[Gavin Smith]

On Fri, Jan 16, 2015 at 11:19 AM, Aharon Robbins <address@hidden> wrote:
> Hi.
>
>> I had a look at the missing script and it decides that the tool has a
>> wrong version if it has exit status 63. This works for some tools like
>> automake and bison.
>
> How do they make this work?
>
automake has a VERSION option (that can be used, e.g., in
AUTOMAKE_OPTIONS in Makefile.am. bison has a command called "%require"
to specify the mininum required version. (Note this is just from me
reading the manuals for these programs, so there's a chance I've
misunderstood.)

>> A quick check of the Gawk manual didn't reveal any
>> way to check for the version when running.
>
> Inside an awk script you can look at PROCINFO["version"]:
>
>         if (! ("version" in PROCINFO) ||
>             PROCINFO["version"] !~ /^[4-9]\./) {
>                 print("This version of awk/gawk won't cut it.") > 
> "/dev/stderr"
>                 exit 1
>         }

This would work even if the PROCINFO array didn't exist right? So it
would work for any version of awk .What if another awk variant,
incompatible with GNU Gawk, uses PROCINFO["version"] for its versions?
(Also the version number check there needs tweaking so that it allows
version "10". :-) ).

On Fri, Jan 16, 2015 at 11:45 AM, Eli Zaretskii <address@hidden> wrote:
> I'd like to add that exit status of 63 is not a requirement: the
> 'missing' script also supports tools that don't, like makeinfo.

The missing script always tries to run the program it is passed, so it
will manage to run an older version of gawk when it shouldn't.

Karl has added a note to README-hacking so a check for this is not essential.