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一个简单例子 para.sh ######################## #!/bin/sh #scriptname:para echo "this script is call $0" echo "$0 $1 $2" echo "The number of positionalparameters is $#" echo "$* is the dollar star" echo "$@ is the dollar at" echo " "$*" is the dollar star which has quoation marks" echo " "$@" is the dollar at which has quoation marks" ################ [root@yqrh5u2]chmod +x para.sh [root@yqrh5u2 rbf]# ./para.sh 1st_name 2nd_para 3rd_last this script is call ./para.sh ./para.sh 1st_name 2nd_para The number of positionalparameters is 3 1st_name 2nd_para 3rd_last is the dollar star 1st_name 2nd_para 3rd_last is the dollar at 1st_name 2nd_para 3rd_last is the dollar star which has quoation marks 1st_name 2nd_para 3rd_last is the dollar at which has quoation marks Positional Parameter What It References $0 References the name of the script,脚本的名称 $# Holds the value of the number of positional parameters，参数的个数 $* Lists all of the positional parameters，列出所有的参数 $@ Means the same as $*, except when enclosed in double quotes "$*" Expands to a single argument (e.g., "$1 $2 $3")， "$@" Expands to separate arguments (e.g., "$1" "$2" "$3") $1 .. $9 References up to nine positional parameters，应用对应的参数 $* and $@ 区别，只有单他们有双引号是才有区别： $ set 'apple pie' pears peaches 6 $ for i in $@ > do > echo $i > done apple pie pears peaches 7 $ set 'apple pie' pears peaches 8 $ for i in "$@" # At last!! > do > echo $i > done apple pie pears peaches 脚本的参数至少是1， name=${1:?"requires an argument" } echo Hello $name :? 将会检验$1是否有值，加入没有，脚本退出，并且报错误信息。 (责任编辑：IT) |