It will be something like this, which turns $flag to 1 when it finds something: 
my $foo = "This is a test.";
my $flag = 0;
print "$flag\t$foo\n";
$flag = ($foo =~ s/a/the/);
print "$flag\t$foo\n";

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But like irah says, you need to provide some code or data if you want more specific help.

In reply to Re: Set the flag by cormanaz
in thread Set the flag by Anonymous Monk

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