#! /bin/bash
# 參數(shù)的使用
# 我們可以在執(zhí)行Shell腳本時(shí),向腳本傳遞參數(shù),腳本內(nèi)獲取參數(shù)的格式為:$n. n代表一個(gè)數(shù)字,1為執(zhí)行腳本的第一個(gè)參數(shù)，2為執(zhí)行腳本的第二個(gè)參數(shù)，以此類(lèi)推
if [ $# != 3 ]; then
    echo "usage: $0 param1 param2 param3"
    echo "e.g: $0 1 2 3"
    exit 1
fi
echo "執(zhí)行文件名： $0"
echo "param1: $1"; echo "param2: $2"; echo "param3: $3"
parameters=$*
# 特殊字符用來(lái)處理參數(shù)
# $#: 傳遞到腳本的參數(shù)個(gè)數(shù)
echo "參數(shù)個(gè)數(shù)為： $#"
# $*: 以一個(gè)單字符串顯示所有向腳本傳遞的參數(shù)
echo "傳遞的參數(shù)作為一個(gè)字符串顯示: $*"
# $@: 與$*相同，但是使用時(shí)加引號(hào)，并在引號(hào)中返回每個(gè)參數(shù)
echo "傳遞的參數(shù)作為字符串顯示: $@"
for i in "$*"; do # 循環(huán)一次
    echo "loop"; echo $i
done
echo ""
for i in "$@"; do # 循環(huán)三次
    echo "loop"; echo $i
done
get_csdn_addr()
{
    echo "csdn addr: https://blog.csdn.net/fengbingchun/"
}

#! /bin/bash
params=(source /bin/bash sh .)
usage()
{
	echo "Error: $0 needs to have an input parameter"
	echo "supported input parameters:"
	for param in ${params[@]}; do
		echo "  $0 ${param}"
	done
	exit -1
}
if [ $# != 1 ]; then
	usage
fi
flag=0
for param in ${params[@]}; do
	if [ $1 == ${param} ]; then
		flag=1
		break
	fi
done
if [ ${flag} == 0 ]; then
	echo "Error: parameter \"$1\" is not supported"
	usage
	exit -1
fi
echo "==== test $1 ===="
$1 parameter_usage.sh 1 2 3
echo "parameters: ${parameters}"
get_csdn_addr
$1 parameter_usage 123
#ret=$?
#if [[ ${ret} != 0 ]]; then
#	echo "##### Error: some of the above commands have gone wrong, please check: ${ret}"
#	exit ${ret}
#fi
if [ $? -ne 0 ]; then
    echo "##### Error: some of the above commands have gone wrong, please check"
	exit -1
fi
echo "test finish"