qcd

国嵌所有的实验代码

#!/bin/sh
#Quick enter your directory. 
#qcd version is 1.00.
#Writen by xiewei 2004. 

setup_content=/etc/qcd
history_dir=$setup_content/history_dir

usage()
{
    echo "qcd(quick cd) version 1.01 command :"
    echo "<qcd -s dir [position]>  add a directory to $history_dir."
    echo "if content = ./, then add current directory to  $history_dir."
    echo "if position(1-20) is not, default value equal 1."
    echo ""
    echo "<qcd -d [position]> then delete a directory from $history_dir."
    echo "if position is not, default value equal last."
    echo ""    
    echo "<qcd -l [position]> then list directory from $history_dir."
    echo  "if position is not, default value equal 1, else list all directory,
          then choice one position's content and enter it."
    echo ""	  
    echo "<qcd -e [position]> then enter a directory from $history_dir."
    echo "if position is not, default value equal 1."
    echo ""    
    echo "<qcd -c> then clear $history_dir."
    exit 1
}


handle()
{
    line_num=`wc -l $history_dir | awk '{print $1}'` #`wc -l $history_dir` 统计$history_dir所指文件的行数
    h_setup_content=/etc/qcd
    h_history_dir=$h_setup_content/history_dir
    tmp=$h_setup_content/tmp
    pos=1
    enter_dir=""
    
    if [ "$1" = "-s" ]    
    then
	[ ! $3 ] || pos=$3    #如果$3为空 pos的值不变，否则pos等于$3
	enter_dir=$2    #输入的DIR
	[ ! "$2" = "./" ] || enter_dir=`pwd`   
	[ ! "$2" = "." ] || enter_dir=`pwd`

	if [ $pos -gt $line_num ]
	then
	    pos=`expr $line_num + 1`
	    echo "$pos  $enter_dir" >> $h_history_dir    #将新的dir追加到$h_history_dir
	    exit 1
	fi


	
	[ ! $line_num -eq 0 ] || ! echo "$pos  $enter_dir" >> $h_history_dir || exit 1
		
	flag=""
	new_num=0
	> $tmp    #将$tmp清空
	cat $h_history_dir | while read num content
	do
	    new_num=`expr $new_num + 1`
	    [ ! $flag ] || num=`expr $num + 1`    #当新添加了一行的时候$new_num + 1
	    [ ! $num -gt 20 ] || exit 1    #当$tmp里面有20行的时候就结束

	    if [ $num -eq $pos ]
	    then
		flag="have"
		echo "$pos  $enter_dir" >> $tmp
	        new_num=`expr $new_num + 1`		
		echo "$new_num  $content" >> $tmp
	    else
		echo "$new_num  $content" >> $tmp
	    fi
	done    

	mv $tmp $h_history_dir
    fi
#*****************************************************************************    
    if [ "$1" = "-l" ]    
    then
	[ ! $2 ] || ! pos=$2 || ! cat $h_history_dir | grep "^$pos " || exit 1    #^只允许在一行的开始匹配字符或单词，grep检测输入
	
	cat  $h_history_dir
    fi
#*****************************************************************************    
    if [ "$1" = "-e" ]    
    then
	if [ $2 ]
	then
	    for x in `cat $h_history_dir | cut -d' ' -f1`    #cut 从标准输入或文本中剪切列或域，-d 指定与空格和TAB不同的域分隔符，-f1剪切第1域
	    do
		if [ "$x" = "$2" ]
		then
             #sed "s/$2 //" ,s 使用替换模式替换相应模式，将$2 替换为空，使用/ / 将要替换的内容括起
			 #sed 替换格式 [ a d d r e s s [，address]] s/ pattern-to-find /replacement-pattern/[g p w n]
		    enter_dir=`cat $h_history_dir | grep "^$2 " | sed "s/$2  //"`   
		    
		    echo "$enter_dir" > $QD
		    exit 1
		fi		    
	    done
	    cat  $h_history_dir
	    echo "Not content number $2"
	    exit 1
	fi
	
    	cat  $h_history_dir
	echo -n "Press <Enter> to exit or enter your choice(1-$line_num/q/Q/): "
	
	while read choice
	do
	    if [ "$choice" = "q"  -o  "$choice" = "Q" ]  
	    then
	        echo "Nothing to do!"
	        exit 1
	    fi

	    [ "$choice" ] ||
	    {
		echo "Nothing to do!"
	        exit 1
	    }
	
	    for x in `cat $h_history_dir | cut -d' ' -f1`
	    do
		if [ "$x" = "$choice" ]
		then

		    enter_dir=`cat $h_history_dir | grep "^$choice  " | sed  "s/$choice  //"`
		    echo "$enter_dir" > $QD
		    exit 1
		fi		    
	    done
	
	    echo -n "Press <Enter> to exit or enter your choice(1-$line_num/q/Q/): "
	done
    fi
#*****************************************************************************    
    if [ "$1" = "-d" ]    
    then
	pos=$line_num
    	[ ! $2 ] || pos=$2
	[ ! $pos -gt $line_num ] || ! echo "in $h_history_dir, only have $line_num  contents " || exit 
	
	new_num=0
	> $tmp
	cat $h_history_dir | while read num content
	do
	    new_num=`expr $new_num + 1`

	    if [ $num -eq $pos ]
	    then
	        new_num=`expr $new_num - 1`		
		echo "delete: $num  $content"
	    else
		echo "$new_num  $content" >> $tmp
	    fi
	done    

	mv $tmp $h_history_dir
    fi
#*****************************************************************************        
    if [ "$1" = "-c" ]    
    then
	echo -n "Are you sure to clear $h_history_dir(y\Y or q\Q)? "
	while read choice
	do
	    if [ "$choice" = "y"  -o  "$choice" = "Y" ]  
	    then
	        > $h_history_dir
		echo "clear $h_history_dir OK!"
		exit 1
	    fi	

	    if [ "$choice" = "q"  -o  "$choice" = "Q" ]  
	    then
	        echo "Nothing to do!"
	        exit 1
	    fi

	    echo -n "Are you sure to clear $h_history_dir(y\Y or q\Q)? "
	done
    fi
}

[ $# -eq 0  ] &&  handle -e #传入参数的个数等于0，

if [ $# -gt 3 ]
then
    usage
fi    


case $1 in
-s)
    [ $2 ] || usage
    handle $1 $2 $3
    ;;
-d)
    [ ! $3 ] || usage
    handle $1 $2
    ;;
-l)    
    [ ! $3 ] || usage
    handle $1 $2
    ;;
-e)
    [ ! $3 ] || usage
    handle $1 $2
    ;;    
-c)
    [ ! $3 ] || usage
    [ ! $2 ] || usage
    handle $1
    ;;
*)    
    usage
    ;;
esac