shell 中$0、$*、$#、$@ 之间的区别
脚本示例
#!/bin/bash
MIN_PARAMS=10
echo
echo "The name of this script is \"`basename $0`\"."
echo
if [ -n "$1" ]; then
echo "param #1 is $1"
fi
if [ -n "$2" ]; then
echo "param #2 is $2"
fi
if [ -n "$3" ]; then
echo "param #3 is $3"
fi
echo "______________________________"
echo "All command-line params are : $*"
echo '$0 =' "$0"
echo '$# =' "$#"
echo '$@ =' "$@"
echo '$* =' "$*"
if [ $# -lt $MIN_PARAMS ]
then
echo
echo "this script need at least $MIN_PARAMS"
fi
exit 0
-
终端直接执行 sh build-Test.sh
The name of this script is "build-Test.sh". ______________________________ All command-line params are : $0 = build-Test.sh $# = 0 $@ = $* = this script need at least 1- $0直接，打印出脚本的名字
build-Test.sh - 判断没有进入
- $#的结果为0
- $@、$*的结果为空
- $0直接，打印出脚本的名字
-
终端直接执行 sh build-Test.sh 1
The name of this script is "build-Test.sh". param #1 is 1 ______________________________ All command-line params are : 1 $0 = build-Test.sh $# = 1 $@ = 1 $* = 1 this script need at least 10- 判断已经执行
- $# = 1，$@ = 1，$* = 1
-
终端直接执行 sh build-Test.sh 1 2
The name of this script is "build-Test.sh". param #1 is 1 param #2 is 2 ______________________________ All command-line params are : 1 2 $0 = build-Test.sh $# = 2 $@ = 1 2 $* = 1 2 this script need at least 10- 判断已经执行
- $# = 2，$@ = 1 2，$* = 1 2
-
终端直接执行 sh build-Test.sh 1 2 3 4 5 6 7 8 9 10
The name of this script is "build-Test.sh". param #1 is 1 param #2 is 2 param #3 is 3 ______________________________ All command-line params are : 1 2 3 4 5 6 7 8 9 10 $0 = build-Test.sh $# = 10 $@ = 1 2 3 4 5 6 7 8 9 10 $* = 1 2 3 4 5 6 7 8 9 10- $0 可用来取出脚本的名字。
- $# 代表参数的数量
- $@和@* 可用来枚举出脚本的参数值
-
if [ -n "%1" ]如果%1的长度非零则返回为真，即非空是真 -
[ INT1 -lt INT2 ]INT1小于INT2返回为真 ,<
shell 条件判断参考资料：http://blog.csdn.net/besfanfei/article/details/8259123
