It means, that I feel sorry for you, because there's a Perl 4 smell ;-)
Seriously, here's the header of my /usr/lib/perl5/5.10.0/getopts.pl:

;# getopts.pl - a better getopt.pl
#
# This library is no longer being maintained, and is included for back
+ward
# compatibility with Perl 4 programs which may require it.
#
# In particular, this should not be used as an example of modern Perl
# programming techniques.
#
# Suggested alternatives: Getopt::Long  or  Getopt::Std
#
;# Usage:
;#      do Getopts('a:bc');  # -a takes arg. -b & -c not. Sets opt_* a
+s a
;#                           #  side effect.

sub Getopts {
 ...
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It is probably a good idea to port the program to use Getopt::Std or Getopt::Long (... there's probably a require "getopts.pl"; somewhere in your program that needs to be replaced) .

Search for occurrences of $opt_* in your program and initialise them with a proper invocation of Getopt::Std::getopts() or Getopt::Long::GetOptions().

Update:   &Getopts('afg:s:n:vb:cd'); means:

flags:

-a, -f, -v, -c, -d

with argument:

-g xxx, -s xxx, -n xxx, -b xxx

Update2: Getopts::Long also allows you to use short flags, so you can keep the interface to your program backward compatible while beeing able to use long options at the same time (I guessed, what the switches might do!):

$result = GetOptions ( "all"      => \$opt_a,
                       "force"    => \$opt_f,
                       "verbose"  => \$opt_v,
                       "check"    => \$opt_c,
                       "debug"    => \$opt_d,

                       "get=s"    => \$opt_g,
                       "source=s" => \$opt_s,
                       "number=i" => \$opt_n,
                       "backup=s" => \$opt_b
);
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