I am trying out your code; I replaced the $listfile with $ARGV[0]. 
#!/usr/bin/perl


# set $listfile to some constant, or to $ARGV[0] (and supply the file
#+name
# as a command-line arg when you run the script)

my %outfh;  # hash to hold output file handles

open ORIGFILE, $ARGV[0] or die "$ARGV[0]: $!";
while ( <ORIGFILE> ) {
    my ( $host, $data ) = split " ", $_, 2;
    if ( ! exists( $outfh{$host} )) {
        open( $outfh{$host}, ">", $host ) or die "$host: $!";
    }
    print $outfh{$host} $data;
}
# perl will flush and close output files when done

[download]
But this produces a syntax error of 
Scalar found where operator expected at ./nocsplit.pl line 17, near "}
+ $data"
        (Missing operator before  $data?)
syntax error at ./nocsplit.pl line 17, near "} $data"
Execution of ./nocsplit.pl aborted due to compilation errors.

[download]
It seems to not like the 
print to $outfh{$host} $data;

[download]

In reply to Re^4: Seperating individual lines of a file by tgrossner
in thread Seperating individual lines of a file by tgrossner

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