Good stuff. Doesn't seem to work for my eval though..

print "Script content: $script_content\n";
print "Script input: $script_input\n";
open(SAVEOUT, ">&STDOUT");
open(SAVEERR, ">&STDERR");
close(STDIN);
open(STDIN, '<',\my $stdin);
#seek STDIN,0,0; # with or without, no diff.
$stdin .= $script_input;
#seek STDIN,0,0; # with or without, no diff.
close(STDOUT);
open(STDOUT,'>' , \my $stdout);
close(STDERR);
open(STDERR,'>' , \my $stderr);
select(STDERR); $| = 1;
select(STDOUT); $| = 1;
eval $script_content;
my $result_code = $@;
close(STDOUT);
close(STDERR);
open(STDOUT, ">&SAVEOUT");
open(STDERR, ">&SAVEERR");
if ( ! $stderr ) { $stderr = ''; } # my db doesn't like nulls.
if ( ! $stdout ) { $stdout = ''; }
print "STDERR:" . $stderr;
print "STDOUT:" . $stdout;
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In all variations where I'm using STDIN that is tied to a variable, I still get the manpage. Argh.

I'm thinking the difference is that in your scenario you can do your writes to STDIN after the process has it. I think I have to have it set up prior to my eval, or my read of stdin within my evaled script will just return as it would get EOF immediately.