Using commandline options in shell scripts

Sample code using getopt

while getopts :f:cuh OP
do
            case ${OP} in
                           f)         SERVERS=${OPTARG}
                                       ;;
                           c)        if [ "${SERVERS}" != "false" ]
                                      then
                                                check
                                       else
                                               usage
                                      fi
                                      ;;
                           u)       if [ "${SERVERS}" != "false" ]
                                     then
                                                cd ${BASE}
                                      fi
                                     ;;
                        *|h)      usage
                                     ;;
                     esac
done

Perl script options

Using getopt in perl scripts.
Sample code

#!/usr/bin/perl
#-------------------------------------------------------------------------
#       Using getop
#-------------------------------------------------------------------------
use Getopt::Std;
getopt('cw');
my @op = `./x.sh -c $opt_c -w $opt_w`;
foreach (@op)
{
        #printf "-c %s\t-w %s\n", $opt_c,$opt_w;
        print $_;
}

Output

./x.pl -c 3 -w 55

in ./x.sh.sh : -c 3 -w 55

-c 3

-w 55

or

my %options=();

#Pre set default values 

my $critv=95;
my $warnv=85;
getopts("c:w:", \%options);
$critv = $options{c} if defined $options{c};
$warnv = $options{w} if defined $options{w};

This method won't report an error if an option is emitted.