linux通过信号来在运行在系统上的进程之间通信也可以通过信号来控制shell脚本的运行
（1）捕捉信号：trap命令
常用信号 ctrl+c（终止进程） ctrl+z（暂停进程，打入后台） [root@server ~]# trap "echo westos" 2 [root@server ~]# ^Cwestos（2）列出中断信号与键盘的关系
[root@server ~]# stty -a speed 38400 baud; rows 24; columns 80; line = 0; intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0; -parenb -parodd -cmspar cs8 -hupcl -cstopb cread -clocal -crtscts -ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc -ixany -imaxbel -iutf8 opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0 isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke（3）信号屏蔽
[root@server ~]# trap "" 2 ##信号屏蔽 [root@server ~]# trap : 2 ##恢复信号（4）脚本形式：
#!/bin/bash trap "echo 'Sorry!I have trapped Ctrl+C'" 2 echo "This is a test script~" count=1 while [ $count -le 10 ] do echo "Loop #$count" sleep 2 count=$[ $count + 1 ] done echo "This is the end of the script~" trap - 2 ##恢复 echo "I just removed the trap"（5）捕捉脚本的退出
[root@server ~]# cat trap.sh trap "echo ByeBye~" EXIT count=1 while [ $count -le 5 ] do echo "Loop #$count" sleep 2 count=$[ $count + 1 ] done [root@server ~]# sh trap.sh Loop #1 Loop #2 Loop #3 ^CByeBye~（6）练习
执行脚本时，使用ctrl+c可以将/tmp/westos下建立的文件都删除掉 #!/bin/bash trap "find /tmp -type f -name "westos_*" | xargs rm -f && exit " 2 while true do touch /tmp/westos_$(date +%F-%N-%M-%S) sleep 2 ls -l /tmp/westos* done