script02

#!/bin/sh

PASSWDFILE=/etc/passwd

print_help()
{
    echo "$0: Usage: $0 [options] | [ login | ps-root ]"
    cat << "END"
Outputs some information, depending on the options.
If no options are specified, the help is printed.

Commands: [ login | ps-root ]
  login:   the /etc/passwd line corresponding to the calling user is printed
  ps-root  the lines of the command `ps-root` containing "root" are printed

Options: [h]
  -h, --help                        outputs this text
END
}

error()
{
    echo $1 >&2
    print_help >&2
}

if [ $# -eq 0 ];then
    print_help
elif [ $# -eq 1 ];then
    if [ "x$1" = "xlogin" ];then
        echo $(cat $PASSWDFILE | egrep "$USER")
    elif [ "x$1" = "xps-root" ];then
        ps -ef | sed -e "root"
    elif [ "x$1" = "x-h" ];then
        print_help
    elif [ "x$1" = "x--help" ];then
        print_help
    else
        error "unknown paremeter"
        exit 1
    fi
else
    error "wrong paremeter count"
    exit 1
fi