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

我发现在脚本中编写可移植解析的问题非常令人沮丧,因此我编写了Argbash-一个FOSS代码生成器,它可以为您的脚本生成参数解析代码,并且具有一些不错的功能:

https://argbash.io

其他回答

这是我使用变量数组对Bruno Bronosky答案的改进解决方案。

它允许您混合参数位置,并为您提供一个参数数组,该数组在没有选项的情况下保持顺序

#!/bin/bash

echo $@

PARAMS=()
SOFT=0
SKIP=()
for i in "$@"
do
case $i in
    -n=*|--skip=*)
    SKIP+=("${i#*=}")
    ;;
    -s|--soft)
    SOFT=1
    ;;
    *)
        # unknown option
        PARAMS+=("$i")
    ;;
esac
done
echo "SKIP            = ${SKIP[@]}"
echo "SOFT            = $SOFT"
    echo "Parameters:"
    echo ${PARAMS[@]}

将输出例如:

$ ./test.sh parameter -s somefile --skip=.c --skip=.obj
parameter -s somefile --skip=.c --skip=.obj
SKIP            = .c .obj
SOFT            = 1
Parameters:
parameter somefile

如果您正在制作可与其他实用程序互换的脚本,下面的灵活性可能很有用。

以下任一项:

command -x=myfilename.ext --another_switch 

Or:

command -x myfilename.ext --another_switch

代码如下:

STD_IN=0

prefix=""
key=""
value=""
for keyValue in "$@"
do
  case "${prefix}${keyValue}" in
    -i=*|--input_filename=*)  key="-i";     value="${keyValue#*=}";; 
    -ss=*|--seek_from=*)      key="-ss";    value="${keyValue#*=}";;
    -t=*|--play_seconds=*)    key="-t";     value="${keyValue#*=}";;
    -|--stdin)                key="-";      value=1;;
    *)                                      value=$keyValue;;
  esac
  case $key in
    -i) MOVIE=$(resolveMovie "${value}");  prefix=""; key="";;
    -ss) SEEK_FROM="${value}";          prefix=""; key="";;
    -t)  PLAY_SECONDS="${value}";           prefix=""; key="";;
    -)   STD_IN=${value};                   prefix=""; key="";; 
    *)   prefix="${keyValue}=";;
  esac
done

我使用前面的答案作为一个起点来整理我以前的即席参数解析。然后我重构了以下模板代码。它使用=或空格分隔的参数以及组合在一起的多个短参数来处理长参数和短参数。最后,它将所有非参数参数重新插入到$1,$2..变量中。

#!/usr/bin/env bash

# NOTICE: Uncomment if your script depends on bashisms.
#if [ -z "$BASH_VERSION" ]; then bash $0 $@ ; exit $? ; fi

echo "Before"
for i ; do echo - $i ; done


# Code template for parsing command line parameters using only portable shell
# code, while handling both long and short params, handling '-f file' and
# '-f=file' style param data and also capturing non-parameters to be inserted
# back into the shell positional parameters.

while [ -n "$1" ]; do
        # Copy so we can modify it (can't modify $1)
        OPT="$1"
        # Detect argument termination
        if [ x"$OPT" = x"--" ]; then
                shift
                for OPT ; do
                        REMAINS="$REMAINS \"$OPT\""
                done
                break
        fi
        # Parse current opt
        while [ x"$OPT" != x"-" ] ; do
                case "$OPT" in
                        # Handle --flag=value opts like this
                        -c=* | --config=* )
                                CONFIGFILE="${OPT#*=}"
                                shift
                                ;;
                        # and --flag value opts like this
                        -c* | --config )
                                CONFIGFILE="$2"
                                shift
                                ;;
                        -f* | --force )
                                FORCE=true
                                ;;
                        -r* | --retry )
                                RETRY=true
                                ;;
                        # Anything unknown is recorded for later
                        * )
                                REMAINS="$REMAINS \"$OPT\""
                                break
                                ;;
                esac
                # Check for multiple short options
                # NOTICE: be sure to update this pattern to match valid options
                NEXTOPT="${OPT#-[cfr]}" # try removing single short opt
                if [ x"$OPT" != x"$NEXTOPT" ] ; then
                        OPT="-$NEXTOPT"  # multiple short opts, keep going
                else
                        break  # long form, exit inner loop
                fi
        done
        # Done with that param. move to next
        shift
done
# Set the non-parameters back into the positional parameters ($1 $2 ..)
eval set -- $REMAINS


echo -e "After: \n configfile='$CONFIGFILE' \n force='$FORCE' \n retry='$RETRY' \n remains='$REMAINS'"
for i ; do echo - $i ; done
while [ "$#" -gt 0 ]; do
  case "$1" in
    -n) name="$2"; shift 2;;
    -p) pidfile="$2"; shift 2;;
    -l) logfile="$2"; shift 2;;

    --name=*) name="${1#*=}"; shift 1;;
    --pidfile=*) pidfile="${1#*=}"; shift 1;;
    --logfile=*) logfile="${1#*=}"; shift 1;;
    --name|--pidfile|--logfile) echo "$1 requires an argument" >&2; exit 1;;
    
    -*) echo "unknown option: $1" >&2; exit 1;;
    *) handle_argument "$1"; shift 1;;
  esac
done

此解决方案:

句柄-n arg和--name=arg允许在末尾使用参数如果有任何拼写错误,则显示正常错误兼容,不使用抨击可读,不需要在循环中维护状态

另一个Shell参数分析器(ASAP)

符合POSIX,无getopt

我受到@bronson相对简单的回答的启发,并试图改进它(不增加太多复杂性)。结果如下:

使用-n[arg]、-abn[arg],--name[arg]和--name=arg样式中的任意一种选项;参数可以按任何顺序出现,循环后$@中只留下位置参数;使用--强制将剩余的参数视为位置参数;检测无效选项和缺少的参数;不依赖于getopt或外部工具(一个功能使用简单的sed命令);便携式,紧凑,可读性强,具有独立功能。

# Convenience functions.
usage_error () { echo >&2 "$(basename $0):  $1"; exit 2; }
assert_argument () { test "$1" != "$EOL" || usage_error "$2 requires an argument"; }

# One loop, nothing more.
if [ "$#" != 0 ]; then
  EOL=$(printf '\1\3\3\7')
  set -- "$@" "$EOL"
  while [ "$1" != "$EOL" ]; do
    opt="$1"; shift
    case "$opt" in

      # Your options go here.
      -f|--flag) flag='true';;
      -n|--name) assert_argument "$1" "$opt"; name="$1"; shift;;

      # Arguments processing. You may remove any unneeded line after the 1st.
      -|''|[!-]*) set -- "$@" "$opt";;                                          # positional argument, rotate to the end
      --*=*)      set -- "${opt%%=*}" "${opt#*=}" "$@";;                        # convert '--name=arg' to '--name' 'arg'
      -[!-]?*)    set -- $(echo "${opt#-}" | sed 's/\(.\)/ -\1/g') "$@";;       # convert '-abc' to '-a' '-b' '-c'
      --)         while [ "$1" != "$EOL" ]; do set -- "$@" "$1"; shift; done;;  # process remaining arguments as positional
      -*)         usage_error "unknown option: '$opt'";;                        # catch misspelled options
      *)          usage_error "this should NEVER happen ($opt)";;               # sanity test for previous patterns

    esac
  done
  shift  # $EOL
fi

# Do something cool with "$@"... \o/

注:我知道。。。二进制模式为0x01030307的参数可能会破坏逻辑。但是,如果有人在命令行中传递这样的参数,他们应该得到它。