In English: If the string $args{DOUBLE_BYTE} has a 'y' or 'Y' in it, sets $tempport to the constant DB_CATPORT, otherwise sets it to SB_CATPORT.

In Perl: 
my $tempport;                      # declare var
if(  $args{DOUBLE_BYTE} =~ /y/i )  # try to match with a regex
                                   # regex is just looking for 'y'
                                   # the /i means case-insensitive
{
  $tempport = DB_CATPORT;         # Set to DB_CATPORT
}
else
{
  $tempport = SB_CATPORT;         # Set to SB_CATPORT
}

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The key uses here are the regex (perldoc perlre) and the ternary operation (perldoc perlop).

Update: Note that $args{DOUBLE_BYTE} represents the value in the %args hash for key 'DOUBLE_BYTE'. (though i guess DOUBLE_BYTE could be a constant, in which case the key is really the constant's value.) Update: thanks Errto! Note to self: don't overthink.

In reply to Re: Snippet explanation please by davidrw
in thread Snippet explanation please by Anonymous Monk

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