I would have written that like this, keeping (and clarifying in the "Usage" message) the intention to allow multiple files to be done in one run. (Note -- on unix/linux/macosx for sure, don't know about "cmd.exe" -- when your command line is  prog_name *.txt or whatever, the shell does file name expansion, replacing "*.txt" with the list of all matching file names, before invoking the script, so @ARGV has that many elements in it.)

#!/usr/bin/perl

use strict;
use String::CRC32;

my $Usage = "Usage: $0 file.name ...\n";
@ARGV or die $Usage;

for my $file ( @ARGV ) {
    open( my $fh, "<", $file ) or die "Unable to open $file: $!\n";
    my $crc = crc32( $fh );
    close $fh;

    printf( "%08x ( %08x ) %s\n", $crc, 0xffffffff - $crc, $file );
}
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I don't understand the relevance of 0xffffffff - $crc, but if it's useful at all, it helps to have fixed-width fields to the left of variable-width fields.