Shell Programming and Scripting

#!/bin/ksh

File=$3

if [ ${#} = 1 ] ; then
      echo "Script"
  
              elif [[ ${2} = -k -o (${2} = -f  && !  $File ) ]] ;then 
                echo "Passed k or f option"
        
                  else "Please check the Input passed"
fi

 elif [[ ${2} = -k -o (${2} = -f && ! = $File ) ]] ;then

  elif [[ (${2} = -k) || (${2} = -f && ! $file ) ]] ;then

#!/bin/ksh
IAm=${0##*/}
err=0
File=""
kflag=
while getopts f:k opt
do      case $opt in
        (f)     File="$OPTARG"
                if [ ! -f "$File" ]
                then    printf "Option -f \"%s\": Not a regular file\n" "$File" >&2
                        err=1
                fi;;
        (k)     kflag=1;;
        (?)     err=2;;
        esac
done
shift $(($OPTIND - 1))
if [ $err -gt 0 ]
then    printf "Usage: %s: [-k] [-f pathname] arg...\n" "$IAm" >&2
        exit $err
fi
if [ "$kflag" ]
then    printf "Option −k found\n"
fi
if [ -n "$File" ]
then    printf "Option -f \"%s\" found; argument is a regular file\n" "$File"
fi
if [ $# -gt 0 ]
then    printf "%d remaining operands are:" $#
        printf " %s" "$*"
        echo
else    echo "No operands found."
fi

#!/usr/bin/somesh  ex. ksh, bash, dash, ...
PRG=$0

#####################
usage()
{
     exitid=$1
     [ "$exitid" = "" ] && exitid=1

     echo " Usage: $PRG -f filename [ -d 0-9 ] [-v ] files" >&2
     echo " or  $PRG --filename filename [ --debug 0-9 ] [--verbose ] files" >&2
     exit $exitid
}

#####################
# set default 
filename=""
verbose=0
debug=0

# parse options: look 1st and shift it, if option need argument then double shift
while [ $# -gt 0 ]
do
        opt="$1"
        case "$opt" in
                -v|--verbose)  verbose=1              ;;
                -d|--debug)    debug="$2" ; shift    ;;
                -f|--filename) filename="$2" ; shift  ;;
                --)   shift; break ;; # options end
                -*)   usage 1 ;;  # unknown option
                *)    break ;;  # arguments ...
        esac
        shift # next option
done

# current status in args :  $* include arguments

# test parameters and if some problem: usage including exit
[ "$filename" = "" ] && usage 2
[ "$debug"    = "" ] && usage 3   # debug value can't be empty
[ "$#"       -lt 1   ] && usage 4   # no argument files

# OK, do it
#  use arguments ex. using for
for arg in $*
do
        echo "arg:$arg"
done