一个shell脚本写的CD管理工具

#!/bin/bash #声明一些全局变量 menu_choice="" current_cd="" title_file="title.cdb" tracks_file="tracks.cdb" tmp_file=/tmp/cdb.$$ #定义当按下ctrl+C捕捉到中断信号时时，删除缓存文件 trap `rm -f $tmp_file` EXIT #两个简单的工具型函数。获取返回值，获取是否确定 get_return(){ echo -e "Press return \c" read x return 0 } get_confirm(){ echo -e "Are you sure? \c" while true do read x case "$x" in y | yes | Y | YES ) return 0;; n | no | N | NO ) echo echo "Cancelled" return 1;; *) echo "Please enter yes or no" ;; esac done } #菜单的内容是动态变化的，当用户选择了某张CD后，主菜单就会多出几个选项 set_menu_choice(){ clear echo "Option -:" echo echo " a) Add a new CD" echo " f) Find CD" echo " c) Count the CDs and tracks in the catalog" if [ "$cdcatnum" != "" ]; then echo " l)List tracks on $cdtitle" echo " r)Remove $cdtitle" echo " u)Update track information for $cdtitle" fi echo " q) Quit" echo echo -e "Please enter choice then press return \c" read menu_choice return } #添加标题和内容的函数 insert_title(){ echo $* >> $title_file return } insert_track(){ echo $* >> $tracks_file return } add_record_tracks(){ echo "Enter track information for this CD" echo " When no more tracks enter q" cdtrack=1 cdtitle="" while [ "$cdtitle" != "q" ] do echo -e "Track $cdtrack,track title? \c" read tmp cdtitle=${tmp%%,*} if [ "$tmp" != "$cdtitle" ];then echo "Sorry,no commas allowed" continue fi if [ -n "$cdtitle" ] ; then if [ "$cdtitle" != "q" ];then insert_track $cdcatnum,$cdtrack,$cdtitle fi else cdtrack=$((cdtrack-1)) fi cdtrack=$((cdtrack+1)) done } #用来输入新的CD唱片的标题信息 add_records(){ #Prompt for the initial information echo -e "Enter catalog name \c" read tmp cdcatnum=${tmp%%,*}; echo -e "Enter title \c" read tmp cdtitle=${tmp%%,*} echo -e "Enter type \c" read tmp cdtype=${tmp%%,*} echo -e "Enter artist/composer \c" read tmp cdac=${tmp%%,*} #check that they want to enter the information echo about to add new entry echo "$cdcatnum $cdtitle $cdtype $cdac" # If confirmed then append it to the titles file if get_confirm ;then insert_title $cdcatnum,$cdtitle,$cdtype,$cdac add_record_tracks else remove_records fi return } #查找函数，在标题文件中查找CD文件中的唱片资料 find_cd(){ if [ "$1" = "n" ];then asklist=n else asklist=y fi cdcatnum="" echo -e "Enter a string to search for in the CD titles \c" read searchstr if [ "$searchstr" = "" ];then return 0 fi grep "$searchstr" $title_file > $tmp_file set $(wc -l $tmp_file) linesfound=$1 case "$linesfound" in 0) echo "Sorry,nothing found" get_return return 0 ;; 1) ;; 2) echo "Sorry not unique." echo "Found the following" cat $tmp_file get_return return 0 esac IFS="," read cdcatnum cdtitle cdtype cdac < $tmp_file IFS=" " if [ -z "$cdcatnum" ];then echo "Sorry,could not extract catalog field form $tmp_file" get_return return 0 fi echo echo Catalog number: $cdcatnum echo Title: $cdtitle echo Type: $cdtype echo Artist/Composer: $cdac echo get_return if [ "$asklist" = "y" ];then echo -e "View tracks for this CD? \c" read x if [ "$x" = "y" ];then echo list_tracks echo fi fi return 1 } #用于重新输入唱片的资料 update_cd(){ if [ -z "$cdcatnum" ];then echo "You must select a CD first" find_cd n fi if [ -n "$cdcatnum" ];then echo "Current tracks are :-" list_tracks echo echo "This will re-enter the tracks for $cdtitle" get_confirm && { grep -v "^${cdcatnum}," $tracks_file > $tmp_file mv $tmp_file $tracks_file echo add_record_tracks } fi return } #快速统计数据库中的唱片个数和曲目总数 count_cds(){ set $(wc -l $title_file) num_titles=$1 set $(wc -l $tracks_file) num_tracks=$1 echo found $num_titles CDs,with a total of $num_tracks tracks get_return return } #从数据库文件中删除数据项 remove_records(){ if [ -z "$cdcatnum" ];then echo You must select a CD first find_cd n fi if [ -n "$cdcatnum" ];then echo "You are about to delete $cdtitle" get_confirm &&{ grep -v "^${cdcatnum}," $title_file > $tmp_file mv $tmp_file $title_file grep -v "^${cdcatnum}," $tracks_file > $tmp_file mv $tmp_file $tracks_file cdcatnum="" echo Entry removed } get_return fi return } #找出想要的行，然后按页输出 list_tracks(){ if [ "$cdcatnum" = "" ];then echo no CD selected yet return else grep "^${cdcatnum}," $tracks_file > $tmp_file num_tracks=$(wc -l $tmp_file) if [ "$num_tracks" = "0" ];then echo no tracks found for $cdtitle else { echo echo "$cdtitle :-" echo cut -f 2- -d, $tmp_file echo } | ${PAGER:-more} fi fi get_return return } #主函数部分 rm -r $tmp_file if [ ! -f $title_file ];then touch $title_file fi if [ ! -f $tracks_file ];then touch $tracks_file fi # now the application proper clear echo echo echo "Mini CD manager" sleep 1 quit=n while [ "$quit" != "y" ]; do set_menu_choice case "$menu_choice" in a) add_records;; r) remove_records;; f) find_cd y;; u) update_cd;; c) count_cds;; l) list_tracks;; b) echo more $title_file echo get_return;; q | Q ) quit=y;; *) echo "Sorry,choice not recognized";; esac done #Tidy up and leave rm -f $tmp_file echo "Finished" exit 0