比如,我有一个脚本,用这行代码调用:

./myscript -vfd ./foo/bar/someFile -o /fizz/someOtherFile

或者这个:

./myscript -v -f -d -o /fizz/someOtherFile ./foo/bar/someFile 

什么是公认的解析方式,以便在每种情况下(或两者的某种组合)$v、$f和$d都将设置为true,而$outFile将等于/fiz/someOtherFile?


当前回答

这里有一个getopts,它用最少的代码实现解析,并允许您在一种情况下使用eval和substring定义要提取的内容。

基本上eval“local key='val'”

function myrsync() {

        local backup=("${@}") args=(); while [[ $# -gt 0 ]]; do k="$1";
                case "$k" in
                    ---sourceuser|---sourceurl|---targetuser|---targeturl|---file|---exclude|---include)
                        eval "local ${k:3}='${2}'"; shift; shift    # Past two arguments
                    ;;
                    *)  # Unknown option  
                        args+=("$1"); shift;                        # Past argument only
                    ;;                                              
                esac                                                
        done; set -- "${backup[@]}"                                 # Restore $@


        echo "${sourceurl}"
}

在这里,将变量声明为局部变量,而不是全局变量。

调用为:

myrsync ---sourceurl http://abc.def.g ---sourceuser myuser ... 

${k:3}基本上是一个从键中删除第一个---的子字符串。

其他回答

有几种方法可以解析cmdline参数(例如GNU getopt(不可移植)vs BSD(MacOS)getopt vs getopts)-所有这些都有问题。此解决方案

是便携式的!没有依赖关系,仅依赖于bash内置允许短期和长期选项处理空格或同时在选项和参数之间使用=分隔符支持串联短选项样式-vxfhandles选项和可选参数(例如--color vs--color=always),正确检测和报告未知选项支持--表示选项结束,以及与相同功能集的替代方案相比,不需要代码膨胀。即简洁,因此易于维护

示例:任何

# flag
-f
--foo

# option with required argument
-b"Hello World"
-b "Hello World"
--bar "Hello World"
--bar="Hello World"

# option with optional argument
--baz
--baz="Optional Hello"

#!/usr/bin/env bash

usage() {
  cat - >&2 <<EOF
NAME
    program-name.sh - Brief description
 
SYNOPSIS
    program-name.sh [-h|--help]
    program-name.sh [-f|--foo]
                    [-b|--bar <arg>]
                    [--baz[=<arg>]]
                    [--]
                    FILE ...

REQUIRED ARGUMENTS
  FILE ...
          input files

OPTIONS
  -h, --help
          Prints this and exits

  -f, --foo
          A flag option
      
  -b, --bar <arg>
          Option requiring an argument <arg>

  --baz[=<arg>]
          Option that has an optional argument <arg>. If <arg>
          is not specified, defaults to 'DEFAULT'
  --     
          Specify end of options; useful if the first non option
          argument starts with a hyphen

EOF
}

fatal() {
    for i; do
        echo -e "${i}" >&2
    done
    exit 1
}

# For long option processing
next_arg() {
    if [[ $OPTARG == *=* ]]; then
        # for cases like '--opt=arg'
        OPTARG="${OPTARG#*=}"
    else
        # for cases like '--opt arg'
        OPTARG="${args[$OPTIND]}"
        OPTIND=$((OPTIND + 1))
    fi
}

# ':' means preceding option character expects one argument, except
# first ':' which make getopts run in silent mode. We handle errors with
# wildcard case catch. Long options are considered as the '-' character
optspec=":hfb:-:"
args=("" "$@")  # dummy first element so $1 and $args[1] are aligned
while getopts "$optspec" optchar; do
    case "$optchar" in
        h) usage; exit 0 ;;
        f) foo=1 ;;
        b) bar="$OPTARG" ;;
        -) # long option processing
            case "$OPTARG" in
                help)
                    usage; exit 0 ;;
                foo)
                    foo=1 ;;
                bar|bar=*) next_arg
                    bar="$OPTARG" ;;
                baz)
                    baz=DEFAULT ;;
                baz=*) next_arg
                    baz="$OPTARG" ;;
                -) break ;;
                *) fatal "Unknown option '--${OPTARG}'" "see '${0} --help' for usage" ;;
            esac
            ;;
        *) fatal "Unknown option: '-${OPTARG}'" "See '${0} --help' for usage" ;;
    esac
done

shift $((OPTIND-1))

if [ "$#" -eq 0 ]; then
    fatal "Expected at least one required argument FILE" \
    "See '${0} --help' for usage"
fi

echo "foo=$foo, bar=$bar, baz=$baz, files=${@}"

我写了一个脚本,可以帮助轻松解析命令行参数https://github.com/unfor19/bargs

示例

$ bash example.sh -n Willy --gender male -a 99
Name:      Willy
Age:       99
Gender:    male
Location:  chocolate-factory
$ bash example.sh -n Meir --gender male
[ERROR] Required argument: age

Usage: bash example.sh -n Willy --gender male -a 99

--person_name  |  -n  [Willy]              What is your name?
--age          |  -a  [Required]
--gender       |  -g  [Required]
--location     |  -l  [chocolate-factory]  insert your location
$ bash example.sh -h

Usage: bash example.sh -n Willy --gender male -a 99
--person_name  |  -n  [Willy]              What is your name?
--age          |  -a  [Required]
--gender       |  -g  [Required]
--location     |  -l  [chocolate-factory]  insert your location

我认为这个很简单:

#!/bin/bash
#

readopt='getopts $opts opt;rc=$?;[ "$rc$opt" = "0?" ]&&exit 1;[ $rc = 0 ]||{ shift $[OPTIND-1];false; }'

opts=vfdo:

# Enumerating options
while eval "$readopt"
do
    echo OPT:$opt ${OPTARG+OPTARG:$OPTARG}
done

# Enumerating arguments
for arg
do
    echo ARG:$arg
done

调用示例:

./myscript -v -do /fizz/someOtherFile -f ./foo/bar/someFile
OPT:v 
OPT:d 
OPT:o OPTARG:/fizz/someOtherFile
OPT:f 
ARG:./foo/bar/someFile

这是我在函数中如何避免在堆栈的较高位置同时中断getopts运行:

function waitForWeb () {
   local OPTIND=1 OPTARG OPTION
   local host=localhost port=8080 proto=http
   while getopts "h:p:r:" OPTION; do
      case "$OPTION" in
      h)
         host="$OPTARG"
         ;;
      p)
         port="$OPTARG"
         ;;
      r)
         proto="$OPTARG"
         ;;
      esac
   done
...
}

我最终实现了公认答案的dash(或/bin/sh)版本,基本上不使用数组:

while [[ $# -gt 0 ]]; do
    case "$1" in
    -v|--verbose) verbose=1; shift;;
    -o|--output) if [[ $# -gt 1 && "$2" != -* ]]; then
            file=$2; shift 2
        else
            echo "-o requires file-path" 1>&2; exit 1
        fi ;;
    --)
        while [[ $# -gt 0 ]]; do BACKUP="$BACKUP;$1"; shift; done
        break;;
    *)
        BACKUP="$BACKUP;$1"
        shift
        ;;
    esac
done
# Restore unused arguments.
while [ -n "$BACKUP" ] ; do
    [ ! -z "${BACKUP%%;*}" ] && set -- "$@" "${BACKUP%%;*}"
    [ "$BACKUP" = "${BACKUP/;/}" ] && break
    BACKUP="${BACKUP#*;}"
done