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?
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
我想提供我的选项解析版本,它允许以下内容:
-s p1
--stage p1
-w somefolder
--workfolder somefolder
-sw p1 somefolder
-e=hello
也允许这样做(可能不需要):
-s--workfolder p1 somefolder
-se=hello p1
-swe=hello p1 somefolder
您必须在使用前决定是否在选项上使用=。这是为了保持代码干净。
while [[ $# > 0 ]]
do
key="$1"
while [[ ${key+x} ]]
do
case $key in
-s*|--stage)
STAGE="$2"
shift # option has parameter
;;
-w*|--workfolder)
workfolder="$2"
shift # option has parameter
;;
-e=*)
EXAMPLE="${key#*=}"
break # option has been fully handled
;;
*)
# unknown option
echo Unknown option: $key #1>&2
exit 10 # either this: my preferred way to handle unknown options
break # or this: do this to signal the option has been handled (if exit isn't used)
;;
esac
# prepare for next option in this key, if any
[[ "$key" = -? || "$key" == --* ]] && unset key || key="${key/#-?/-}"
done
shift # option(s) fully processed, proceed to next input argument
done
其他回答
来自digitalpeer.com,稍作修改:
用法myscript.sh-p=my_prefix-s=dirname-l=libname
#!/bin/bash
for i in "$@"
do
case $i in
-p=*|--prefix=*)
PREFIX="${i#*=}"
;;
-s=*|--searchpath=*)
SEARCHPATH="${i#*=}"
;;
-l=*|--lib=*)
DIR="${i#*=}"
;;
--default)
DEFAULT=YES
;;
*)
# unknown option
;;
esac
done
echo PREFIX = ${PREFIX}
echo SEARCH PATH = ${SEARCHPATH}
echo DIRS = ${DIR}
echo DEFAULT = ${DEFAULT}
要更好地理解${i#*=},请在本指南中搜索“Substring Removal”。它在功能上等同于调用一个不需要的子流程的‘sed’s/[^=]*=//'<<<“$i”`或调用两个不需要子流程的“echo”$i”|sed’s/[^=]*=//'`。
当我尝试这个问题时,上面的答案似乎有点bug——这是我发现更强大的解决方案:
boolean_arg=""
arg_with_value=""
while [[ $# -gt 0 ]]
do
key="$1"
case $key in
-b|--boolean-arg)
boolean_arg=true
shift
;;
-a|--arg-with-value)
arg_with_value="$2"
shift
shift
;;
-*)
echo "Unknown option: $1"
exit 1
;;
*)
arg_num=$(( $arg_num + 1 ))
case $arg_num in
1)
first_normal_arg="$1"
shift
;;
2)
second_normal_arg="$1"
shift
;;
*)
bad_args=TRUE
esac
;;
esac
done
# Handy to have this here when adding arguments to
# see if they're working. Just edit the '0' to be '1'.
if [[ 0 == 1 ]]; then
echo "first_normal_arg: $first_normal_arg"
echo "second_normal_arg: $second_normal_arg"
echo "boolean_arg: $boolean_arg"
echo "arg_with_value: $arg_with_value"
exit 0
fi
if [[ $bad_args == TRUE || $arg_num < 2 ]]; then
echo "Usage: $(basename "$0") <first-normal-arg> <second-normal-arg> [--boolean-arg] [--arg-with-value VALUE]"
exit 1
fi
如果您正在制作可与其他实用程序互换的脚本,下面的灵活性可能很有用。
以下任一项:
command -x=myfilename.ext --another_switch
Or:
command -x myfilename.ext --another_switch
代码如下:
STD_IN=0
prefix=""
key=""
value=""
for keyValue in "$@"
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
Bash空格分隔(例如--option参数)
cat >/tmp/demo-space-separated.sh <<'EOF'
#!/bin/bash
POSITIONAL_ARGS=()
while [[ $# -gt 0 ]]; do
case $1 in
-e|--extension)
EXTENSION="$2"
shift # past argument
shift # past value
;;
-s|--searchpath)
SEARCHPATH="$2"
shift # past argument
shift # past value
;;
--default)
DEFAULT=YES
shift # past argument
;;
-*|--*)
echo "Unknown option $1"
exit 1
;;
*)
POSITIONAL_ARGS+=("$1") # save positional arg
shift # past argument
;;
esac
done
set -- "${POSITIONAL_ARGS[@]}" # restore positional parameters
echo "FILE EXTENSION = ${EXTENSION}"
echo "SEARCH PATH = ${SEARCHPATH}"
echo "DEFAULT = ${DEFAULT}"
echo "Number files in SEARCH PATH with EXTENSION:" $(ls -1 "${SEARCHPATH}"/*."${EXTENSION}" | wc -l)
if [[ -n $1 ]]; then
echo "Last line of file specified as non-opt/last argument:"
tail -1 "$1"
fi
EOF
chmod +x /tmp/demo-space-separated.sh
/tmp/demo-space-separated.sh -e conf -s /etc /etc/hosts
复制粘贴上面的块的输出
FILE EXTENSION = conf
SEARCH PATH = /etc
DEFAULT =
Number files in SEARCH PATH with EXTENSION: 14
Last line of file specified as non-opt/last argument:
#93.184.216.34 example.com
用法
demo-space-separated.sh -e conf -s /etc /etc/hosts
Bash等于分隔符(例如,--option=argument)
cat >/tmp/demo-equals-separated.sh <<'EOF'
#!/bin/bash
for i in "$@"; do
case $i in
-e=*|--extension=*)
EXTENSION="${i#*=}"
shift # past argument=value
;;
-s=*|--searchpath=*)
SEARCHPATH="${i#*=}"
shift # past argument=value
;;
--default)
DEFAULT=YES
shift # past argument with no value
;;
-*|--*)
echo "Unknown option $i"
exit 1
;;
*)
;;
esac
done
echo "FILE EXTENSION = ${EXTENSION}"
echo "SEARCH PATH = ${SEARCHPATH}"
echo "DEFAULT = ${DEFAULT}"
echo "Number files in SEARCH PATH with EXTENSION:" $(ls -1 "${SEARCHPATH}"/*."${EXTENSION}" | wc -l)
if [[ -n $1 ]]; then
echo "Last line of file specified as non-opt/last argument:"
tail -1 $1
fi
EOF
chmod +x /tmp/demo-equals-separated.sh
/tmp/demo-equals-separated.sh -e=conf -s=/etc /etc/hosts
复制粘贴上面的块的输出
FILE EXTENSION = conf
SEARCH PATH = /etc
DEFAULT =
Number files in SEARCH PATH with EXTENSION: 14
Last line of file specified as non-opt/last argument:
#93.184.216.34 example.com
用法
demo-equals-separated.sh -e=conf -s=/etc /etc/hosts
要更好地理解${i#*=},请在本指南中搜索“Substring Removal”。它在功能上等同于调用一个不需要的子流程的‘sed’s/[^=]*=//'<<<“$i”`或调用两个不需要子流程的“echo”$i”|sed’s/[^=]*=//'`。
将bash与getopt[s]一起使用
getopt(1)限制(较旧、较新的getopt版本):
无法处理空字符串的参数无法处理带有嵌入空格的参数
最近的getopt版本没有这些限制。有关更多信息,请参阅这些文档。
POSIX获取选项
此外,POSIX外壳和其他提供的getopts没有这些限制。我包含了一个简单的getopts示例。
cat >/tmp/demo-getopts.sh <<'EOF'
#!/bin/sh
# A POSIX variable
OPTIND=1 # Reset in case getopts has been used previously in the shell.
# Initialize our own variables:
output_file=""
verbose=0
while getopts "h?vf:" opt; do
case "$opt" in
h|\?)
show_help
exit 0
;;
v) verbose=1
;;
f) output_file=$OPTARG
;;
esac
done
shift $((OPTIND-1))
[ "${1:-}" = "--" ] && shift
echo "verbose=$verbose, output_file='$output_file', Leftovers: $@"
EOF
chmod +x /tmp/demo-getopts.sh
/tmp/demo-getopts.sh -vf /etc/hosts foo bar
复制粘贴上面的块的输出
verbose=1, output_file='/etc/hosts', Leftovers: foo bar
用法
demo-getopts.sh -vf /etc/hosts foo bar
getopts的优点是:
它更便于携带,可以在其他外壳中使用,如dash。它可以以典型的Unix方式自动处理多个单一选项,如-vf文件名。
getopts的缺点是它只能处理短选项(-h,而不是-help),而无需额外代码。
有一个getopts教程,它解释了所有语法和变量的含义。在bash中,还有帮助getopts,这可能会提供信息。