Linux case 及 函数位置参数

位置参数

$0, $1, $2,等等...
位置参数,从命令行传递给脚本,或者是传递给函数.或者赋职给一个变量.
(具体见Example 4-5 和Example 11-15)
$#
命令行或者是位置参数的个数.(见Example 33-2)
$*
所有的位置参数,被作为一个单词.
注意:"$*"必须被""引用.
$@
与$*同义,但是每个参数都是一个独立的""引用字串,这就意味着参数被完整地传递,
并没有被解释和扩展.这也意味着,每个参数列表中的每个参数都被当成一个独立的
单词.
注意:"$@"必须被引用.

具体见代码：

#!/bin/bash
# arglist.sh

E_BADARGS=65

if [ ! -n "$1" ]
then
  echo "Usage: `basename $0` argument1 argument2 etc."
  exit $E_BADARGS
fi

echo

index=1

echo "Listing args with \"\$*\":"
for arg in "$*"
do
  echo "Arg #$index = $arg"
  let "index+=1"
done
echo "Entire arg list seen as single word."

echo

index=1


echo "Listing args with \"\$@\":"
for arg in "$@"
do
  echo "Arg #$index = $arg"
  let "index+=1"
done
echo "Arg list seen as separate words."

echo

index=1

echo "Listing args with \$* (unquoted):"
for arg in $*
do
  echo "Arg #$index = $arg"
  let "index+=1"
done
echo "Arg list seen as separate words."

exit 0

#!/bin/bash
echo 'begin work '
binHome=`dirname $0`
echo $binHome
cd $binHome
binHome=`pwd`
echo $binHome

workHome=${binHome}/..
echo $workHome
b=${workHome}/common/date.sh
echo $b
source ${workHome}/common/date.sh
index=1
for arg in $*
do
  if [[ "x$arg" == "x" ]]; then
    exit 1
  else
    case $index in
        1)
            loadDate=$arg
            ;;
        2)
            days=$arg
            ;;
        *)
            execFile=$arg
            execDate=${loadDate}
            for ((i=0;i<days;i=i+1))
            do
              bash ${execFile} ${execDate}
              execDate=`dashDateAdd ${execDate} '1'` 
            done
            ;;
    esac
    let "index+=1"
  fi
done
exit 0