while : do echo "This is another infinite loop." sleep 1 done 在这两个例子中,true和:命令总是返回状态码0(表示成功),因此循环会无限进行下去。 说明如何安全地中断bash中的无限循环: 要安全地中断Bash中的无限循环,可以使用Ctrl+C组合键。这将发送一个中断信号给正在运行的脚本或命令,强制其停止执行。
最简单的永远循环之一是使用while命令,后面跟上条件true。 你不必使用诸如while [ 1 -eq 1 ]之类的逻辑或类似的测试。while true测试表示循环将一直运行,直到你使用CTRL-C停止循环、关闭终端窗口或注销为止。这是一个例子: $ while true > do > echo Keep running > sleep 3 > done Keep running Keep runnin...
I wrote a really simple file explorer using ls with a shell script. I used a while loop to make the script run forever (until Ctrl+C), but the while loop doesn't seem to work. I get this error ./fileexplorer: line 5: syntax error near unexpected token `done' ./fileexplorer: line...
The file contents ofcars.txtmatch the printout of the while loop script. 20. Delete Files To delete an existing file, you can use anifstatement to check if the file exists and instruct the bash script to remove it. Start by creating the bash script file: nano deletefiles.sh The followin...
Similarly for example we can use while loop to check if file does not exists. This script will sleep until file does exists. Note bash negator "!" which negates the -e option. #!/bin/bash while [ ! -e myfile ]; do # Sleep until file does exists/is created ...
If you want to do something more elaborate, you could create a script and show a more clear indication that the loop condition became true: #!/bin/bashwhile[!-ddirectory_expected]doecho"`date`- Still waiting"sleep1doneecho"DIRECTORY IS THERE!!!" ...
#!/bin/bash # 启动后台进程 sleep 10 & echo "Background job started" # 等待后台进程结束 wait echo "All background jobs finished" 3. 处理终止信号 确保脚本正确处理终止信号。例如: 代码语言:txt 复制 #!/bin/bash # 信号处理函数 terminate() { echo "Terminating script..." exit 0 } # 捕获...
I have a simple bash script that listens to SIGUSR{1,2} like this: #!/usr/bin/env bash trigger() { echo "receiving signal" } echo $$ trap trigger USR1 USR2 sleep inf So I ran the script and then ran: kill -USR1 -$PID # where $PID is the PID printed by the script rece...
/bin/bashcdsleep3ls pwd 小quiz:假设我现在在/home/yourname/dir1/dir2/dir3/下,并且运行cd命令后,我会回到/home/yourname/。那么请问上面这个例子中的bash script运行完后,我会在哪里? 可以动手试一试。也许结果和想的不一样。 除了上面的./example.sh的方法,另一种运行bash script的方式是bash example....
6.循环loop 6.1 while do done, until do done (不定循环) 6.2 for...in...do...done (固定循环) 6.5 for...do...done 的数值处理 7.shell script的追踪与debug 四、补充 1.打印进度条 2.文件描述符(参考第一章18小节) 3.进程检测