Shell command getopts Usage

Write shell scripts Common sh test.sh

The notation of-M 2-d 3

Case script:

#!/bin/bashwhile getopts ": a:b:c:" Arg #选项后面的冒号表示该选项需要参数doecho  "arg": $arg case        $arg in             a)                echo "a ' s ARG: $OPTARG---$OPTIND "#参数存在 $OPTARG                ;;             b)                echo "B ' s arg: $OPTARG---  $OPTIND"                ;;             c)                echo "C ' s ARG: $OPTARG---$OPTIND";;     ?)  #当有不认识的选项的时候arg为?            echo "unkonw argument"        exit 1        ;;        Esacdone

The getopts consists of two constants:

$OPTARG: Save the value of the current option

$OPTIND: The displacement of the parameter list, the initial value is 1, the index value of the next parameter

Getopts ": a:b:c:": The first colon is the error message is ignored, the last colon is the last parameter can be obtained, the argument is an empty move index gets the value of the last parameter

Shell command getopts Usage