Something like this is probably more what you are looking for: 
my $sop = ...
my $sport = ...

while( <FH> ) {
    # get the 9th element
    my $port_a = (split /:/)[8];
    # do the eval and capture the return value of comparison
    my $result = eval "\$port_a $sop \$sport";
    # exit if eval failed
    die "eval error: $@" if $@;                 
    if( $result ) {
        # do something
    } else {
        # do something
    }
}

[download]
You have to escape the variables you dont want eval to replace (string interpolate). And the "if" statement is redunant. You can just return the boolean value of the comparison.

In reply to Re: How to do that with eval ? by perlmonkey
in thread How to do that with eval ? by iwanthome

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