Shell Programming and Scripting

 
#!/bin/bash
args="$@" # save arguments to variable 
## Read input arguments, if so 
while [ $# -ge 1 ]; do 
    case $1 in 
        -v | --verbose ) verbose=true;; 
        -z | --gzip ) compression="gz";; 
        -b | --bzip2 ) compression="bz";; 
        -n | --no-compress) compression="none";;
        -h | --help ) showUsage; exit 0 ;; 
        *) echoErr "Invalid option $1. Use -h or --help to show usage"; exit 1 ;; 
    esac
    shift
done

args="$@" # store into args variable
# [...] previous while
argsIterate=($args) # I don't know how to iterate over $args, except convert into an array
for (( i=0;i<${#argsIterate[@]};i++)); do # 1st loop over all arguments
    for (( j=i+1;j<${#argsIterate[@]};j++)); do # 2nd loop over rest arguments
        if ([ "${argsIterate[${i}]}" == "-z" ] && ([ "${argsIterate[${j}]}" == "-b" ] || [ "${argsIterate[${j}]}" == "-n" ])) || \
                ([ "${argsIterate[${i}]}" == "-b" ] && ([ "${argsIterate[${j}]}" == "-z" ] || [ "${argsIterate[${j}]}" == "-n" ])) || \
                ([ "${argsIterate[${i}]}" == "-n" ] && ([ "${argsIterate[${j}]}" == "-z" ] || [ "${argsIterate[${j}]}" == "-b" ])) ; then 
            echo "Incompatible arguments ${argsIterate[${i}]} and ${argsIterate[${j}]}"
            exit -1; 
        fi
    done
done

#!/bin/bash

die() {
        echo "$@" >&2
        exit 1
}

## Read input arguments
while [ $# -ge 1 ]; do 
    case "$1" in 
        -v | --verbose ) verbose=true;; 
        -z | --gzip )
                [ -z "$compression" ] || die "Conflicting option $1"
                compression="gz";; 
        -b | --bzip2 )
                [ -z "$compression" ] || die "Conflicting option $1"
                compression="bz";; 
        -n | --no-compress)
                [ -z "$compression" ] || die "Conflicting option $1"
                compression="none";;
        -h | --help ) showUsage; exit 0 ;; 
        *) die "Invalid option $1. Use -h or --help to show usage" ;; 
    esac
    shift
done

/some/command -xy

/some/command -x -y

#! /bin/ksh
typeset aflag=""
typeset bflag=""
typeset bval=""
typeset curropt=""
typeset -i OPTIND=0       # number of passed args

while getopts ab: curropt ; do
     case $curropt in
          a)
               aflag=1
               ;;

          b)
               bflag=1
               bval="$OPTARG"
               ;;

         ?)
               printf "Usage: %s: [-a] [-b value] args\n" $0
               exit 2
               ;;
     esac
done

if [ ! -z "$aflag" ] ; then
     printf "Option -a specified\n"
fi

if [ ! -z "$bflag" ]; then
     printf 'Option -b "%s" specified\n' "$bval"
fi

shift $(($OPTIND -1))           # clear cmdline
exit 0