Unless statement in Perl

unless statement in perl behaves just opposite to the if statement in perl. It executes the set of statements inside its body when the given condition is false.

unless(condition) {
   statement(s);
}

The statements inside unless body would execute when the condition is false.

Example

#!/usr/local/bin/perl

printf "Enter any number:";
$num = <STDIN>;
unless($num>=100) {
   printf "num is less than 100\n";
}

Output:

Enter any number:99
num is less than 100