use Getopt::Long qw(GetOptions);
Getopt::Long::Configure(qw(posix_default no_ignore_case));

GetOptions(\my %OPT,
    "mandatory!",
);

die "Option --mandatory not specified.\n"
  unless exists $OPT{mandatory};

print "OK.\n";

[download]

On the command line:
$ testcmd.pl
Option --mandatory not specified.

$ testcmd.pl --manda
Unknown option: manda
Option --mandatory not specified.

$ testcmd.pl --mandatorY
Unknown option: mandatorY
Option --mandatory not specified.

$ testcmd.pl --mandatory
OK.

$ testcmd.pl --nomandatory
OK.

[download]

In reply to Re: using "Getopt::Long" how to check parameter mandatory by repellent
in thread using "Getopt::Long" how to check parameter mandatory by shan_emails

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