Use the CGI module.
To retrieve parameters sent to the script, do: 
use CGI;
my $q = new CGI;
my %param = $q->Vars;

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To check whether the params were sent via POST, do: 
my $method = $q->request_method();

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which should give either 'POST', 'GET' or 'HEAD'.

In reply to Re: Detecting a post via cgi by fireartist
in thread Detecting a post via cgi by jcpunk

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