shell结

#!/bin/bash


prints()
{
         str="str1";
        echo "Hello"${str}
}


prints
echo ${str}
~                                                                                                                                   
wang@linux:~/test> ./testexit.sh  
Hellostr1

str1        

 #!/bin/bash


prints()
{
        local str="str1";
        echo "Hello"${str}
}


prints
echo ${str}
~               

 wang@linux:~/test> ./testexit.sh    
Hellostr1      

anadict.sh

#! /bin/bash


DICT=/usr/share/dict/words
COUNT=false
GROUP=false
WHERE=false
usage() {
    echo "usage: $0 [-c] [-w <where clause>] [-g <group by clause>]"
    echo -e "\tEXAMPLE"
    echo -e "\t$0 -c -w 's$ -g 1:3"
    echo -e "\tmeans"
    echo -e "\tselect count(*) where word like '%\'s' group by substr(word,0,3)"
}


where() {
    [ $WHERE = true ] && grep "$GREP" $1 || cat $1 
}


count() {
    wc -l --
}


toGroupKey() {
    IFS=: read offset length <<< $GRBY
    while read w
    do
if [ -z $length ];then
   k=${w:$offset}
else
   k=${w: $offset:$length}
fi
echo "${k}" | grep -v ^$
    done
}


groupByCount() {
    sort | uniq -c
}


[ $# -eq 0 ] && usage && exit 1


while getopts ":cw:g:" opt
do
    case $opt in
c ) COUNT=true
   ;;
w)
   WHERE=true
   GREP=$OPTARG
   ;;
g)
   GROUP=true
   GRBY=$OPTARG
   ;;
*)
   usage
   exit 1
   ;;
    esac
done


if [ $GROUP != true ]; then 
    where $DICT | ([ $COUNT = true ] && count || cat )
else
    where $DICT | toGroupKey | ([ $COUNT = true ] && groupByCount || cat )
fi
exit 0