D'oh! This is true, problem is lacking in problem. The problem is that I'm not getting a new console window for the shelled program. Everything's staying in the original console (which I care less about), and more to the point not turning STDIN back over to the keyboard, which makes interactive programs like aspell much harder to use. This means that "perl -w aspell_filter.pl README.TXT" works just fine, but "type README.TXT | perl -w aspell_filter.pl" doesn't. The latter is, unfortunately, the whole reason for putting this together in the first place. I've taken the variable of aspell out of the mix by replacing the call with CMD.EXE for now, just to see what's going on. Here's the entire program again, with the changes, and all of the initial 'use's.

use strict;
use IO::File;
use File::Temp qw(tempfile);
use Win32::Process;
use Win32;

# Create a temporary file to hold the input.
my ($fh, $filename) = tempfile();

# And stream everything into it.
my $linecount = 0;
while (<>)    {
    $fh->print($_);
    $linecount++;
}

print STDERR "Wrote $linecount lines to $filename.\n";

# Now pass the input off to aspell for processing
my $obj;
my $appname = "C:\\windows\\system32\\cmd.exe";
my $cmdline = "/K dir";
my $iflags = 0;
my $cflags = NORMAL_PRIORITY_CLASS + CREATE_NEW_CONSOLE;
my $curdir = ".";

Win32::Process::Create(    $obj,
                        $appname,
                        $cmdline,
                        $iflags,
                        $cflags,
                        $curdir)
                        or die "Couldn't shell to aspell.\n";

$obj->Wait(INFINITE);

# Return the tempfile on standard output
seek($fh, 0, 0);
while (<$fh>) {
    print
}

print "Check complete."
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Sorry for the initial screwup. Anyone got any thoughts? I'm not tied to the idea of a second console, or using Win32::Process directly, I'm just looking for the moral equivalent of:

STDIN = console input;
STDOUT = console display;
system("stuff");
STDOUT = back to the redirected version;
[download]