代码： 全选
#!/bin/sh
#定义全局变量
menu_choice=""
current_cd=""
title_file="title.cdb" #标题文件
tracks_file="track.cdb" #曲目文件
temp_file=/tmp/cdb.$$ #临时文件
trap 'rm -f $temp_file' EXIT #当按下Ctrl+C组合键的中断处理，保证删除临时文件再退出
#全局变量定义结束
#定义函数开始
get_return() { # get_return() 函数
echo -e "Press return 请按回车键 \c" #按回车键返回
read x
return 0
}
get_confirm() { # get_confirm() 函数 用于确认用户操作或者确认信息
echo -e "Are you sure? \c" #有些shell可能不支持echo -e
while true
do
read x #读入用户输入
case "$x" in
y | yes | Y | Yes | YES )
return 0;;
n | no | N | No | NO )
echo
echo "Cancelled"
return 1;;
*) echo "Please enter yes or no" ;;
esac
done
}
set_menu_choice() { # 设置菜单选项
clear
echo "Options :-"
echo
echo " a) Add new CD 添加一张新CD"
echo " f) Find CD 查找CD"
echo " c) Count the CDs and tracks in the catalog 在目录中统计CD和曲目的数目"
if [ "$cdcatnum" != "" ]; then #如果CD唱片目录不为空
echo " l) List tracks on $cdtitle 根据CD标题列出曲目"
echo " r) Remove $cdtitle 删除CD标题"
echo " u) Update track information for $cdtitle 更新曲目信息"
fi
echo " q) Quit 退出"
echo
echo -e "Please enter choice then press return \c"
read menu_choice #读入用户选项
return
}
insert_title() {
echo $* >> $title_file
return
}
insert_track() { #插入曲目
echo $* >> $tracks_file #追加到$tracks_file
}
add_record_tracks() { #添加曲目的函数
echo "Enter track information for this CD"
echo "When no more tracks enter q"
cdtrack=1
cdttitle=""
while [ "$cdttitle" != "q" ]
do
echo -e "Track $cdtrack,track title? 输入曲目标题\c" ################# 错误已改正 ################
read tmp
cdttitle=${tmp%%,*} #从尾部开始查找匹配 ,* 的格式并删除，返回剩余部分赋值给$cdttitle
if [ "$tmp" != "$cdttitle" ]; then #如果删除逗号后二者不相符，则输出提示
echo "$tmp\n$cdttitle"
echo "Sorry,no commas allowed 不允许包含逗号"
continue
fi ################# 错误已改正 ################
if [ -n "$cdttitle" ]; then # 如果$cdttitle 长度非零返回真，如果是 -z 替换 -n 表示长度为零时返回真
if [ "$cdttitle" != "q" ]; then #如果输入不为q
insert_track $cdcatnum,$cdtrack,$cdttitle
fi
else
cdtrack=$((cdtrack-1)) # $(($cdtrack-1)) 据我测试是等价
fi
cdtrack=$((cdtrack+1))
done
}
add_records() { #添加记录的函数
# Prompt for the initial information 初始化信息提示
echo -e "Enter catalog name 请输入目录名称 \c"
read tmp #读入一个临时变量
cdcatnum=${tmp%%,*} #从尾部开始搜索匹配并删除，返回赋值给cdcatnum
echo -e "Enter title 请输入标题 \c"
read tmp
cdtitle=${tmp%%,*}
echo -e "Enter type 请输入类型 \c"
read tmp
cdtype=${tmp%%,*}
echo -e "Enter artist/composer 请输入作曲或者作词或者演唱者 \c"
read tmp
cdac=${tmp%%,*}
#Check that they want to enter the information 输出确认信息
echo About to add new entry
echo "$cdcatnum $cdtitle $cdtype $cdac"
#If confirmed then append it to the titles file 如果确认则添加信息
if get_confirm ; then #调用get_confirm函数
insert_title $cdcatnum,$cdtitle,$cdtype,$cdac
add_record_tracks
else
remove_records
fi
return
}
find_cd() { #查找CD函数
if [ "$1" = "n" ]; then
asklist=n
else
asklist=y
fi
cdcatnum=""
echo -e "Enter a string to search for in the CD titles 请输入要查找的唱片标题 \c"
read searchstr
if [ "$searchstr" = "" ]; then
return 0
fi
grep "$searchstr" $title_file > $temp_file #从$title_file中搜索与搜索关键字匹配的向，然后重定向到$temp_file
set $(wc -l $temp_file) # 括号中 wc -l 是统计行数
linesfound=$1 # $1 表示函数的第一个参数，依此类推
case "$linesfound" in #看查找到几项匹配的记录
0) echo "Sorry,nothing found"
get_return
return 0
;;
1) ;;
2) echo "Sorry,not unique"
echo "Found the following"
cat $temp_file
get_return
return 0
esac
IFS="," #设置分割符为逗号
read cdcatnum cdtitle cdtype cdac < $temp_file
IFS=" " #设置分割符为空格
if [ -z "$cdcatnum" ]; then #如果$cdcatnum的长度为零则返回真
echo "Sorry,could not extract catalog field from $temp_file 不能从 $temp_file 中提取出目录"
get_return #返回
return 0
fi
echo
echo Catalog number目录数量: $cdcatnum
echo Title标题: $cdtitle
echo Type类型: $cdtype
echo Artist/Composer艺术家/作者: $cdac
echo
get_return
if [ "$asklist" = "y" ]; then
echo -e "View tracks for this CD? 查看这张CD的曲目？ \c"
read x
if [ "$x" = "y" ]; then
echo
list_tracks
echo
fi
fi
return 1
}
update_cd() { #更新CD的函数
if [ -z "$cdcatnum" ]; then #如果$cdcatnum为零则返回真
echo "You must select a CD first你必须选择一张CD"
find_cd n #调用find_cd()函数，参数为n
fi
if [ -n "$cdcatnum" ]; then #如果$cdcatnum不为零则返回真
echo "Current tracks are 现在的曲目有 :-"
list_tracks #调用列曲目函数
echo
echo "This will re-enter the tracks for $cdtitle 重输入曲目"
get_confirm && { #确认而且……
grep -v "^${cdcatnum}," $tracks_file > $temp_file #参数 -v 对匹配模式取反，即搜索不匹配行；此外 -i表示忽略大小写，-l表示只输出包含匹配行的文件，而不输出真正的匹配行，-c表示输出匹配行的数目
mv $temp_file $tracks_file #重命名
echo
add_record_tracks #添加曲目
}
fi
return
}
count_cds() {
set $(wc -l $title_file) #统计$title_file文件的行数并返回，并利用set命令将其设置为$1
num_titles=$1
set $(wc -l $tracks_file)
num_tracks=$1
echo found $num_titles CDs,with a total of $num_tracks tracks
get_return
return
}
remove_records() {
if [ -z "$cdcatnum" ]; then #如果$cdcatnum为零则返回真
echo You must select a CD first
find_cd n
fi
if [ -n "$cdcatnum" ]; then #如果不为零则返回真
echo "You are about to delete $cdtitle"
get_confirm && {
grep -v "^${cdcatnum}," $title_file > $temp_file #-v表示取反模式开启
mv $temp_file $title_file
grep -v "^${cdcatnum}," $tracks_file > $temp_file
mv $temp_file $tracks_file
cdcatnum=""
echo Entry removed
}
get_return
fi
return
}
list_tracks() {
if [ "$cdcatnum" = "" ]; then
echo no CD selected yet
return
else
grep "^${cdcatnum}," $tracks_file > $temp_file
num_tracks=$(wc -l $temp_file)
if [ "$num_tracks" = "0" ]; then
echo "no tracks found for $cdtitle"
else {
echo
echo "$cdtitle :-"
echo
cut -f 2- -d , $temp_file
echo
} | ${PAGER:-more} #如果PAGER未被设置则取默认值more
fi
fi
get_return
return
}
# 函数定义结束
#开始主函数部分
rm -f $temp_file #删除临时文件 $temp_file
if [ ! -f $title_file ]; then #如果$title_file不存在
touch $title_file #创建$title_file
fi
if [ ! -f $tracks_file ]; then #如果$tracks_file不存在
touch $tracks_file #创建$tracks_file
fi
# Now the application proper 程序OK了
clear #清屏
echo
echo
echo "Mini CD manager"
sleep 1
quit=n #默认设置quit标记为n，即不退出
while [ "$quit" != "y" ];
do
set_menu_choice #调用函数输出菜单
case "$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选择无法被解释";;
esac
done
#Tidy up and leave 清除干净再离开
rm -f $temp_file
echo "Finished"
exit 0
