我想这样调用myscript文件:

$ ./myscript -s 45 -p any_string

or

$ ./myscript -h  #should display help
$ ./myscript     #should display help

我的要求是:

Getopt在这里获取输入参数 检查-s是否存在,如果不存在则返回错误 检查-s后面的值是否为45或90 检查-p是否存在并且后面有一个输入字符串 如果用户输入。/myscript -h或。/myscript,则显示帮助

我尝试了到目前为止这段代码:

#!/bin/bash
while getopts "h:s:" arg; do
  case $arg in
    h)
      echo "usage" 
      ;;
    s)
      strength=$OPTARG
      echo $strength
      ;;
  esac
done

但是使用这些代码,我会得到错误。怎么和巴斯一起去?


当前回答

原始代码的问题是:

H:在不应该的地方期望参数,因此将其更改为H(不带冒号) 要使用-p any_string,需要将p:添加到参数列表中

基本上:在选项后面意味着它需要参数。


getopts的基本语法是(参见:man bash):

getopts OPTSTRING VARNAME [ARGS...]

地点:

OPTSTRING is string with list of expected arguments, h - check for option -h without parameters; gives error on unsupported options; h: - check for option -h with parameter; gives errors on unsupported options; abc - check for options -a, -b, -c; gives errors on unsupported options; :abc - check for options -a, -b, -c; silences errors on unsupported options; Notes: In other words, colon in front of options allows you handle the errors in your code. Variable will contain ? in the case of unsupported option, : in the case of missing value. OPTARG - is set to current argument value, OPTERR - indicates if Bash should display error messages.

所以代码可以是:

#!/usr/bin/env bash
usage() { echo "$0 usage:" && grep " .)\ #" $0; exit 0; }
[ $# -eq 0 ] && usage
while getopts ":hs:p:" arg; do
  case $arg in
    p) # Specify p value.
      echo "p is ${OPTARG}"
      ;;
    s) # Specify strength, either 45 or 90.
      strength=${OPTARG}
      [ $strength -eq 45 -o $strength -eq 90 ] \
        && echo "Strength is $strength." \
        || echo "Strength needs to be either 45 or 90, $strength found instead."
      ;;
    h | *) # Display help.
      usage
      exit 0
      ;;
  esac
done

使用示例:

$ ./foo.sh 
./foo.sh usage:
    p) # Specify p value.
    s) # Specify strength, either 45 or 90.
    h | *) # Display help.
$ ./foo.sh -s 123 -p any_string
Strength needs to be either 45 or 90, 123 found instead.
p is any_string
$ ./foo.sh -s 90 -p any_string
Strength is 90.
p is any_string

参见:Bash Hackers Wiki上的小getopts教程

其他回答

#!/bin/bash

usage() { echo "Usage: $0 [-s <45|90>] [-p <string>]" 1>&2; exit 1; }

while getopts ":s:p:" o; do
    case "${o}" in
        s)
            s=${OPTARG}
            ((s == 45 || s == 90)) || usage
            ;;
        p)
            p=${OPTARG}
            ;;
        *)
            usage
            ;;
    esac
done
shift $((OPTIND-1))

if [ -z "${s}" ] || [ -z "${p}" ]; then
    usage
fi

echo "s = ${s}"
echo "p = ${p}"

示例运行:

$ ./myscript.sh
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -h
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -s "" -p ""
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -s 10 -p foo
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -s 45 -p foo
s = 45
p = foo

$ ./myscript.sh -s 90 -p bar
s = 90
p = bar

在马克·G。的评论(在Adrian Frühwirth的答案下)变成了一个更可读的答案-这展示了如何避免使用getopts来获得可选参数:

usage() { 
    printf "Usage: %s <req> [<-s|--sopt> <45|90>] [<-p|--popt> <string>]\n" "$0"; 
    return 1; 
}; 

main() { 
    req="${1:?$(usage)}";
    shift; 
    s="";
    p="";
    while [ "$#" -ge 1 ]; do
        case "$1" in 
            -s|--sopt) 
                shift;
                s="${1:?$(usage)}";
                [ "$s" -eq 45 ] || [ "$s" -eq 90 ] || { 
                    usage; 
                    return 1; 
                } 
                ;; 
            -p|--popt) 
                shift; 
                p="${1:?$(usage)}" 
                ;; 
            *) 
                usage;
                return 1 
                ;; 
        esac; 
        shift;
    done; 
    printf "req = %s\ns = %s\np = %s\n" "$req" "$s" "$p"; 
};

main "$@"

正如n.caillou的评论所指出的:

如果选项和参数之间没有空格,它就会失败。

然而,为了使它更符合POSIX(来自Mark G。的其他评论):

        case "$1" in 
            -s*)
                s=${1#-s}; 
                if [ -z "$s" ]; 
                    shift; 
                    s=$1; 
                fi

POSIX 7示例

同样值得检查标准中的示例:http://pubs.opengroup.org/onlinepubs/9699919799/utilities/getopts.html

aflag=
bflag=
while getopts ab: name
do
    case $name in
    a)    aflag=1;;
    b)    bflag=1
          bval="$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))
printf "Remaining arguments are: %s\n" "$*"

然后我们可以试一下:

$ sh a.sh
Remaining arguments are: 
$ sh a.sh -a
Option -a specified
Remaining arguments are: 
$ sh a.sh -b
No arg for -b option
Usage: a.sh: [-a] [-b value] args
$ sh a.sh -b myval
Option -b "myval" specified
Remaining arguments are: 
$ sh a.sh -a -b myval
Option -a specified
Option -b "myval" specified
Remaining arguments are: 
$ sh a.sh remain
Remaining arguments are: remain
$ sh a.sh -- -a remain
Remaining arguments are: -a remain

在Ubuntu 17.10中测试,sh是dash 0.5.8。

原始代码的问题是:

H:在不应该的地方期望参数,因此将其更改为H(不带冒号) 要使用-p any_string,需要将p:添加到参数列表中

基本上:在选项后面意味着它需要参数。


getopts的基本语法是(参见:man bash):

getopts OPTSTRING VARNAME [ARGS...]

地点:

OPTSTRING is string with list of expected arguments, h - check for option -h without parameters; gives error on unsupported options; h: - check for option -h with parameter; gives errors on unsupported options; abc - check for options -a, -b, -c; gives errors on unsupported options; :abc - check for options -a, -b, -c; silences errors on unsupported options; Notes: In other words, colon in front of options allows you handle the errors in your code. Variable will contain ? in the case of unsupported option, : in the case of missing value. OPTARG - is set to current argument value, OPTERR - indicates if Bash should display error messages.

所以代码可以是:

#!/usr/bin/env bash
usage() { echo "$0 usage:" && grep " .)\ #" $0; exit 0; }
[ $# -eq 0 ] && usage
while getopts ":hs:p:" arg; do
  case $arg in
    p) # Specify p value.
      echo "p is ${OPTARG}"
      ;;
    s) # Specify strength, either 45 or 90.
      strength=${OPTARG}
      [ $strength -eq 45 -o $strength -eq 90 ] \
        && echo "Strength is $strength." \
        || echo "Strength needs to be either 45 or 90, $strength found instead."
      ;;
    h | *) # Display help.
      usage
      exit 0
      ;;
  esac
done

使用示例:

$ ./foo.sh 
./foo.sh usage:
    p) # Specify p value.
    s) # Specify strength, either 45 or 90.
    h | *) # Display help.
$ ./foo.sh -s 123 -p any_string
Strength needs to be either 45 or 90, 123 found instead.
p is any_string
$ ./foo.sh -s 90 -p any_string
Strength is 90.
p is any_string

参见:Bash Hackers Wiki上的小getopts教程

Getopts和getopt非常有限。虽然建议完全不要使用getopt,但它确实提供了长选项。而getopts只允许单字符选项,如-a -b。使用这两种方法都有一些缺点。

所以我写了一个小脚本来替换getopts和getopt。 这是一个开始,它可能会有很大的改进。

更新08-04-2020:我已经添加了对连字符的支持,例如——package-name。

使用方法:"./script.sh package install——package "name with space" ——建立档案”

# Example:
# parseArguments "${@}"
# echo "${ARG_0}" -> package
# echo "${ARG_1}" -> install
# echo "${ARG_PACKAGE}" -> "name with space"
# echo "${ARG_BUILD}" -> 1 (true)
# echo "${ARG_ARCHIVE}" -> 1 (true)
function parseArguments() {
  PREVIOUS_ITEM=''
  COUNT=0
  for CURRENT_ITEM in "${@}"
  do
    if [[ ${CURRENT_ITEM} == "--"* ]]; then
      printf -v "ARG_$(formatArgument "${CURRENT_ITEM}")" "%s" "1" # could set this to empty string and check with [ -z "${ARG_ITEM-x}" ] if it's set, but empty.
    else
      if [[ $PREVIOUS_ITEM == "--"* ]]; then
        printf -v "ARG_$(formatArgument "${PREVIOUS_ITEM}")" "%s" "${CURRENT_ITEM}"
      else
        printf -v "ARG_${COUNT}" "%s" "${CURRENT_ITEM}"
      fi
    fi

    PREVIOUS_ITEM="${CURRENT_ITEM}"
    (( COUNT++ ))
  done
}

# Format argument.
function formatArgument() {
  ARGUMENT="${1^^}" # Capitalize.
  ARGUMENT="${ARGUMENT/--/}" # Remove "--".
  ARGUMENT="${ARGUMENT//-/_}" # Replace "-" with "_".
  echo "${ARGUMENT}"
}