I have no idea why you're so hellbent on painting this as an XY problem. The OP needs to receive input. The OP is used to receiving it via CGI.pm. The OP understands that CGI.pm is deprecated and wants to know the current, non-deprecated alternative which comes closest to working in the same way.

None of that is application-dependent, nor does it suggest that there's a "real question" behind the question of "how do I accept user input?".

Sorry for not replying promptly. I was out of work for a few days.

Yes -- my problem is "What's the recommended way to receive HTTP input on multiple channels, while abstracting away which channel(s) was used?".

My CGI script is tiny, has one entry point, it's not a full service, not a big application.

Preferred way would be:

#!/usr/bin/perl

use CGI:Somesolution qw(getAllInputAsHash); 

# user input, decoded from UTF
my $userinput = getAllInputAsHash({decodeUtf => 1});
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I keep using CGI.pm like this:

#!/usr/bin/perl 

use CGI; 
use Encode; 

my $cgi = CGI->new;

sub decodedForSomeTypes { 
    $ENV{CONTENT_TYPE} =~ /boundary/ ? $_[0] : decode_utf8($_[0]); 
}

my $params = +{
    map { $_ => decodedForSomeTypes(scalar $cgi->param($_)) } $cgi->pa
+ram()
};
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Since you mention Unicode: Just the other day I became aware of the new CGI::Tiny, which seems to place emphasis on Unicode.