我研究那个课题已经很长时间了。并制作了我自己的库，你将需要在你的主脚本的来源。 有关示例，请参见libopt4shell和cd2mpc。 希望能有所帮助!

我想要一个没有外部依赖关系、有严格bash支持(-u)的东西，而且我需要它能在较旧的bash版本上工作。这个函数处理各种类型的参数:

短bool (-h) 短选项(-i "image.jpg") 长boos(——救命) = options(——file="filename.ext") 空格选项(——file "filename.ext") 连接的bool (-hvm)

只需在脚本顶部插入以下内容:

# Check if a list of params contains a specific param
# usage: if _param_variant "h|?|help p|path f|file long-thing t|test-thing" "file" ; then ...
# the global variable $key is updated to the long notation (last entry in the pipe delineated list, if applicable)
_param_variant() {
  for param in $1 ; do
    local variants=${param//\|/ }
    for variant in $variants ; do
      if [[ "$variant" = "$2" ]] ; then
        # Update the key to match the long version
        local arr=(${param//\|/ })
        let last=${#arr[@]}-1
        key="${arr[$last]}"
        return 0
      fi
    done
  done
  return 1
}

# Get input parameters in short or long notation, with no dependencies beyond bash
# usage:
#     # First, set your defaults
#     param_help=false
#     param_path="."
#     param_file=false
#     param_image=false
#     param_image_lossy=true
#     # Define allowed parameters
#     allowed_params="h|?|help p|path f|file i|image image-lossy"
#     # Get parameters from the arguments provided
#     _get_params $*
#
# Parameters will be converted into safe variable names like:
#     param_help,
#     param_path,
#     param_file,
#     param_image,
#     param_image_lossy
#
# Parameters without a value like "-h" or "--help" will be treated as
# boolean, and will be set as param_help=true
#
# Parameters can accept values in the various typical ways:
#     -i "path/goes/here"
#     --image "path/goes/here"
#     --image="path/goes/here"
#     --image=path/goes/here
# These would all result in effectively the same thing:
#     param_image="path/goes/here"
#
# Concatinated short parameters (boolean) are also supported
#     -vhm is the same as -v -h -m
_get_params(){

  local param_pair
  local key
  local value
  local shift_count

  while : ; do
    # Ensure we have a valid param. Allows this to work even in -u mode.
    if [[ $# == 0 || -z $1 ]] ; then
      break
    fi

    # Split the argument if it contains "="
    param_pair=(${1//=/ })
    # Remove preceeding dashes
    key="${param_pair[0]#--}"

    # Check for concatinated boolean short parameters.
    local nodash="${key#-}"
    local breakout=false
    if [[ "$nodash" != "$key" && ${#nodash} -gt 1 ]]; then
      # Extrapolate multiple boolean keys in single dash notation. ie. "-vmh" should translate to: "-v -m -h"
      local short_param_count=${#nodash}
      let new_arg_count=$#+$short_param_count-1
      local new_args=""
      # $str_pos is the current position in the short param string $nodash
      for (( str_pos=0; str_pos<new_arg_count; str_pos++ )); do
        # The first character becomes the current key
        if [ $str_pos -eq 0 ] ; then
          key="${nodash:$str_pos:1}"
          breakout=true
        fi
        # $arg_pos is the current position in the constructed arguments list
        let arg_pos=$str_pos+1
        if [ $arg_pos -gt $short_param_count ] ; then
          # handle other arguments
          let orignal_arg_number=$arg_pos-$short_param_count+1
          local new_arg="${!orignal_arg_number}"
        else
          # break out our one argument into new ones
          local new_arg="-${nodash:$str_pos:1}"
        fi
        new_args="$new_args \"$new_arg\""
      done
      # remove the preceding space and set the new arguments
      eval set -- "${new_args# }"
    fi
    if ! $breakout ; then
      key="$nodash"
    fi

    # By default we expect to shift one argument at a time
    shift_count=1
    if [ "${#param_pair[@]}" -gt "1" ] ; then
      # This is a param with equals notation
      value="${param_pair[1]}"
    else
      # This is either a boolean param and there is no value,
      # or the value is the next command line argument
      # Assume the value is a boolean true, unless the next argument is found to be a value.
      value=true
      if [[ $# -gt 1 && -n "$2" ]]; then
        local nodash="${2#-}"
        if [ "$nodash" = "$2" ]; then
          # The next argument has NO preceding dash so it is a value
          value="$2"
          shift_count=2
        fi
      fi
    fi

    # Check that the param being passed is one of the allowed params
    if _param_variant "$allowed_params" "$key" ; then
      # --key-name will now become param_key_name
      eval param_${key//-/_}="$value"
    else
      printf 'WARNING: Unknown option (ignored): %s\n' "$1" >&2
    fi
    shift $shift_count
  done
}

像这样使用它:

# Assign defaults for parameters
param_help=false
param_path=$(pwd)
param_file=false
param_image=true
param_image_lossy=true
param_image_lossy_quality=85

# Define the params we will allow
allowed_params="h|?|help p|path f|file i|image image-lossy image-lossy-quality"

# Get the params from arguments provided
_get_params $*

这需要一些时间，但我想要全部:

短选项 长选项 不管有没有论点 非选项参数(没有“-”或“——”的参数) 顺序不重要(script.sh /file -V或script.sh -V /file) 抓住错误用法 在不同的脚本中使用它作为模块，而不需要更改多行代码

最后，我提出了下面的解决方案，它使用getopt来捕获错误并将非选项移动到列表的末尾，然后再使用getopts来解析短选项和长选项。

所有的选项都会自动解析，将它们的长选项名作为变量名(请看例子):

# create string of short options
opt_short=$(printf "%s" "${!options[@]}")

# create string of long options
opt_long="$(printf ",%s" "${options[@]}")"

# catch wrong options and move non-options to the end of the string
args=$(getopt -l "$opt_long" "$opt_short" "$@" 2> >(sed -e 's/^/stderr/g')) || echo -n "Error: " && echo "$args" | grep -oP "(?<=^stderr).*" && exit 1

# create new array of options
mapfile -t args < <(xargs -n1 <<< "$(echo "$args" | sed -E "s/(--[^ ]+) '/\1='/g")" )

# overwrite $@ (options)
set -- "${args[@]}"

# parse options ([h]=help sets the variable "$opt_help" and [V]="" sets the variable "$opt_V")
while getopts "$opt_short-:" opt; do

  echo "$opt:$OPTARG"

  # long option
  if [[ "$opt" == "-" ]]; then

    # extract long option name
    opt="${OPTARG%%=*}"

    # extract long option argument (may be empty)
    OPTARG="${OPTARG#"$opt"}"

    # remove "=" from long option argument
    OPTARG="${OPTARG#=}"

    # set variable name
    opt=opt_$opt

  # short option without argument uses long option name as variable name
  elif [[ "${options[$opt]+x}" ]] && [[ "${options[$opt]}" ]]; then
    opt=opt_${options[$opt]} 

  # short option with argument uses long option name as variable name
  elif [[ "${options[$opt:]+x}" ]] && [[ "${options[$opt:]}" ]]; then
    opt=opt_${options[$opt:]} 

  # short option without long option name uses short option name as variable name
  else
    opt=opt_$opt
  fi

  # remove double colon
  opt="${opt%:}" 

  # options without arguments are set to 1
  [[ ! $OPTARG ]] && OPTARG=1 

  # replace hyphen against underscore
  opt="${opt//-/_}"

  # set variable variables (replaces hyphen against underscore)
  printf -v "$opt" '%s' "$OPTARG" 

done

现在，我只需要定义所需的选项名称和源代码脚本:

# import options module
declare -A options=( [h]=help [f:]=file: [V]=verbose [0]=long_only: [s]="" )
source "/usr/local/bin/inc/options.sh";

# display help text
if [[ $opt_help ]]; then
  echo "help text"
  exit
fi

# output
echo "opt_help:$opt_help"
echo "opt_file:$opt_file"
echo "opt_verbose:$opt_verbose"
echo "opt_long_only:$opt_long_only"
echo "opt_short_only:$opt_s"
echo "opt_path:$1"
echo "opt_mail:$2"

在调用脚本时，可以完全随机地传递所有选项和非选项:

#             $opt_file     $1        $2       $opt_V  $opt_long_only $opt_s
# /demo.sh --file=file.txt /dir info@example.com -V --long_only=yes -s
opt_help:1
opt_file:file.txt
opt_verbose:1
opt_long_only:yes
opt_short_only:1
opt_path=/dir
opt_mail:info@example.com

笔记

在选项数组中，在选项名称后添加:以启用参数。 如果没有给出较长的选项名，则变量名将是$opt_X，其中X是较短的选项名。 如果您希望使用较长的选项名而不定义较短的选项名，则将数组索引设置为一个数字，如上面示例中使用[0]=long_only所做的那样。当然，每个数组下标必须是唯一的。

使用的技术

不使用临时文件捕获stderr 将字符串转换为数组 使用:来解析getopt参数 使用getopts解析长选项名

公认的答案很好地指出了bash内置getopts的所有缺点。答案以:

因此，虽然可以编写更多的代码来解决长选项支持不足的问题，但工作量要大得多，并且在一定程度上违背了使用getopt解析器来简化代码的目的。

尽管我原则上同意这种说法，但我觉得我们在各种脚本中实现这个特性的次数证明，我们应该花一些精力来创建一个“标准化”的、经过良好测试的解决方案。

因此，我通过在纯bash中实现getopts_long“升级”了内置在getopts中的bash，没有外部依赖。该函数的使用与内置的getopts 100%兼容。

通过在脚本中包含getopts_long(在GitHub上托管)，可以简单地实现原始问题的答案:

source "${PATH_TO}/getopts_long.bash"

while getopts_long ':c: copyfile:' OPTKEY; do
    case ${OPTKEY} in
        'c'|'copyfile')
            echo 'file supplied -- ${OPTARG}'
            ;;
        '?')
            echo "INVALID OPTION -- ${OPTARG}" >&2
            exit 1
            ;;
        ':')
            echo "MISSING ARGUMENT for option -- ${OPTARG}" >&2
            exit 1
            ;;
        *)
            echo "Misconfigured OPTSPEC or uncaught option -- ${OPTKEY}" >&2
            exit 1
            ;;
    esac
done

shift $(( OPTIND - 1 ))
[[ "${1}" == "--" ]] && shift

可以考虑以下三种实现方式:

Bash内置的getopts。这不支持带有双破折号前缀的长选项名。它只支持单字符选项。 BSD UNIX实现的独立getopt命令(这是MacOS使用的)。这也不支持长选项。 独立getopt的GNU实现。GNU getopt(3)(由Linux上的命令行getopt(1)使用)支持解析长选项。

其他一些答案给出了使用bash内置getopts模拟长选项的解决方案。该解决方案实际上生成了一个字符为“-”的短选项。所以你得到“——”作为标志。然后，后面的所有内容都变成OPTARG，并使用嵌套的case测试OPTARG。

这很聪明，但也需要注意:

getopts不能强制执行opt规范。如果用户提供了无效的选项，它不能返回错误。在解析OPTARG时，您必须自己进行错误检查。 OPTARG用于长选项名称，当长选项本身有参数时，这会使使用复杂化。你最终不得不自己编写代码作为一个额外的案例。

因此，虽然可以编写更多的代码来解决长选项支持不足的问题，但工作量要大得多，并且在一定程度上违背了使用getopt解析器来简化代码的目的。

为了保持跨平台兼容性，避免依赖外部可执行文件，我从另一种语言移植了一些代码。

我发现它很容易使用，这里有一个例子:

ArgParser::addArg "[h]elp"    false    "This list"
ArgParser::addArg "[q]uiet"   false    "Supress output"
ArgParser::addArg "[s]leep"   1        "Seconds to sleep"
ArgParser::addArg "v"         1        "Verbose mode"

ArgParser::parse "$@"

ArgParser::isset help && ArgParser::showArgs

ArgParser::isset "quiet" \
   && echo "Quiet!" \
   || echo "Noisy!"

local __sleep
ArgParser::tryAndGetArg sleep into __sleep \
   && echo "Sleep for $__sleep seconds" \
   || echo "No value passed for sleep"

# This way is often more convienient, but is a little slower
echo "Sleep set to: $( ArgParser::getArg sleep )"

所需的BASH有点长，但我希望避免依赖BASH 4的关联数组。你也可以直接从http://nt4.com/bash/argparser.inc.sh下载

#!/usr/bin/env bash

# Updates to this script may be found at
# http://nt4.com/bash/argparser.inc.sh

# Example of runtime usage:
# mnc.sh --nc -q Caprica.S0*mkv *.avi *.mp3 --more-options here --host centos8.host.com

# Example of use in script (see bottom)
# Just include this file in yours, or use
# source argparser.inc.sh

unset EXPLODED
declare -a EXPLODED
function explode 
{
    local c=$# 
    (( c < 2 )) && 
    {
        echo function "$0" is missing parameters 
        return 1
    }

    local delimiter="$1"
    local string="$2"
    local limit=${3-99}

    local tmp_delim=$'\x07'
    local delin=${string//$delimiter/$tmp_delim}
    local oldifs="$IFS"

    IFS="$tmp_delim"
    EXPLODED=($delin)
    IFS="$oldifs"
}


# See: http://fvue.nl/wiki/Bash:_Passing_variables_by_reference
# Usage: local "$1" && upvar $1 "value(s)"
upvar() {
    if unset -v "$1"; then           # Unset & validate varname
        if (( $# == 2 )); then
            eval $1=\"\$2\"          # Return single value
        else
            eval $1=\(\"\${@:2}\"\)  # Return array
        fi
    fi
}

function decho
{
    :
}

function ArgParser::check
{
    __args=${#__argparser__arglist[@]}
    for (( i=0; i<__args; i++ ))
    do
        matched=0
        explode "|" "${__argparser__arglist[$i]}"
        if [ "${#1}" -eq 1 ]
        then
            if [ "${1}" == "${EXPLODED[0]}" ]
            then
                decho "Matched $1 with ${EXPLODED[0]}"
                matched=1

                break
            fi
        else
            if [ "${1}" == "${EXPLODED[1]}" ]
            then
                decho "Matched $1 with ${EXPLODED[1]}"
                matched=1

                break
            fi
        fi
    done
    (( matched == 0 )) && return 2
    # decho "Key $key has default argument of ${EXPLODED[3]}"
    if [ "${EXPLODED[3]}" == "false" ]
    then
        return 0
    else
        return 1
    fi
}

function ArgParser::set
{
    key=$3
    value="${1:-true}"
    declare -g __argpassed__$key="$value"
}

function ArgParser::parse
{

    unset __argparser__argv
    __argparser__argv=()
    # echo parsing: "$@"

    while [ -n "$1" ]
    do
        # echo "Processing $1"
        if [ "${1:0:2}" == '--' ]
        then
            key=${1:2}
            value=$2
        elif [ "${1:0:1}" == '-' ]
        then
            key=${1:1}               # Strip off leading -
            value=$2
        else
            decho "Not argument or option: '$1'" >& 2
            __argparser__argv+=( "$1" )
            shift
            continue
        fi
        # parameter=${tmp%%=*}     # Extract name.
        # value=${tmp##*=}         # Extract value.
        decho "Key: '$key', value: '$value'"
        # eval $parameter=$value
        ArgParser::check $key
        el=$?
        # echo "Check returned $el for $key"
        [ $el -eq  2 ] && decho "No match for option '$1'" >&2 # && __argparser__argv+=( "$1" )
        [ $el -eq  0 ] && decho "Matched option '${EXPLODED[2]}' with no arguments"        >&2 && ArgParser::set true "${EXPLODED[@]}"
        [ $el -eq  1 ] && decho "Matched option '${EXPLODED[2]}' with an argument of '$2'"   >&2 && ArgParser::set "$2" "${EXPLODED[@]}" && shift
        shift
    done
}

function ArgParser::isset
{
    declare -p "__argpassed__$1" > /dev/null 2>&1 && return 0
    return 1
}

function ArgParser::getArg
{
    # This one would be a bit silly, since we can only return non-integer arguments ineffeciently
    varname="__argpassed__$1"
    echo "${!varname}"
}

##
# usage: tryAndGetArg <argname> into <varname>
# returns: 0 on success, 1 on failure
function ArgParser::tryAndGetArg
{
    local __varname="__argpassed__$1"
    local __value="${!__varname}"
    test -z "$__value" && return 1
    local "$3" && upvar $3 "$__value"
    return 0
}

function ArgParser::__construct
{
    unset __argparser__arglist
    # declare -a __argparser__arglist
}

##
# @brief add command line argument
# @param 1 short and/or long, eg: [s]hort
# @param 2 default value
# @param 3 description
##
function ArgParser::addArg
{
    # check for short arg within long arg
    if [[ "$1" =~ \[(.)\] ]]
    then
        short=${BASH_REMATCH[1]}
        long=${1/\[$short\]/$short}
    else
        long=$1
    fi
    if [ "${#long}" -eq 1 ]
    then
        short=$long
        long=''
    fi
    decho short: "$short"
    decho long: "$long"
    __argparser__arglist+=("$short|$long|$1|$2|$3")
}

## 
# @brief show available command line arguments
##
function ArgParser::showArgs
{
    # declare -p | grep argparser
    printf "Usage: %s [OPTION...]\n\n" "$( basename "${BASH_SOURCE[0]}" )"
    printf "Defaults for the options are specified in brackets.\n\n";

    __args=${#__argparser__arglist[@]}
    for (( i=0; i<__args; i++ ))
    do
        local shortname=
        local fullname=
        local default=
        local description=
        local comma=

        explode "|" "${__argparser__arglist[$i]}"

        shortname="${EXPLODED[0]:+-${EXPLODED[0]}}" # String Substitution Guide: 
        fullname="${EXPLODED[1]:+--${EXPLODED[1]}}" # http://tldp.org/LDP/abs/html/parameter-substitution.html
        test -n "$shortname" \
            && test -n "$fullname" \
            && comma=","

        default="${EXPLODED[3]}"
        case $default in
            false )
                default=
                ;;
            "" )
                default=
                ;;
            * )
                default="[$default]"
        esac

        description="${EXPLODED[4]}"

        printf "  %2s%1s %-19s %s %s\n" "$shortname" "$comma" "$fullname" "$description" "$default"
    done
}

function ArgParser::test
{
    # Arguments with a default of 'false' do not take paramaters (note: default
    # values are not applied in this release)

    ArgParser::addArg "[h]elp"      false       "This list"
    ArgParser::addArg "[q]uiet" false       "Supress output"
    ArgParser::addArg "[s]leep" 1           "Seconds to sleep"
    ArgParser::addArg "v"           1           "Verbose mode"

    ArgParser::parse "$@"

    ArgParser::isset help && ArgParser::showArgs

    ArgParser::isset "quiet" \
        && echo "Quiet!" \
        || echo "Noisy!"

    local __sleep
    ArgParser::tryAndGetArg sleep into __sleep \
        && echo "Sleep for $__sleep seconds" \
        || echo "No value passed for sleep"

    # This way is often more convienient, but is a little slower
    echo "Sleep set to: $( ArgParser::getArg sleep )"

    echo "Remaining command line: ${__argparser__argv[@]}"

}

if [ "$( basename "$0" )" == "argparser.inc.sh" ]
then
    ArgParser::test "$@"
fi