Use symlinks on the clients. Change the shebang line to the fixed location of the symlink (#!/usr/local/bin/my-shiny-perl in my example). Make the symlink point to the perl interpreter you want to use. It does not matter where the interpreter is installed (locally or on the NFS server).

$^O happens when perl is already running, so that's too late. You choose perl by the local symlink.

Of course, you can have some kind of installer script that actually creates the local symlink. Something like this (untested):

#!/usr/bin/env perl
# ^-- use any perl available
use strict;
use warnings;

my $shinyperl=($^O eq 'linux') ? '/nfs/linux/bin/perl' : '/nfs/aix/bin
+/perl';
symlink($shinyperl,'/usr/local/bin/my-shiny-perl') or die "Create syml
+ink failed: $!";
[download]

Alexander

Another option, if you want to avoid local symlinks at all costs, is to use the default shell and make that decide which perl to run, using the uname command:

#!/bin/sh
if [ "$(uname)" = "Linux" ] ; then
    perl="/nfs/linux/bin/perl"
else
    perl="/nfs/aix/bin/perl"
fi
exec "$perl" /nfs/commom/perl/the-script.pl "$@"
[download]

You can merge this loader script and the perl code into a single script, see perlrun. This will look something like this:

#!/bin/sh
if [ "$(uname)" = "Linux" ] ; then
    perl="/nfs/linux/bin/perl"
else
    perl="/nfs/aix/bin/perl"
fi
exec "$perl" -x $0 "$@"
#!perl
# ^- "perl -x" searches for this line. Linux and AIX don't care about 
+this line.
use strict;
use warnings;
print "Hello World!\n";
[download]

I don't know much about AIX. You may need to replace "$@" with ${1+"$@"}, see perlrun and http://www.in-ulm.de/~mascheck/various/bourne_args/. Also, uname and even test ([] may behave different than on linux.

Alexander

Thanks a ton Alexander! It worked!