一遍又一遍地运行/关闭程序

Question

有没有办法可以编写一个简单的脚本来运行程序，大约5秒后关闭该程序，然后重复？

我只是希望能够运行我一遍又一遍地编写的程序，但是这样做我必须在运行它后5秒钟关闭它。

谢谢！

Answer 1

如果您的命令是非交互式（无需用户交互）：

使用控制操作符&在后台中启动您的程序，通过$!可以访问其PID（进程ID），通过该操作可以终止运行睡眠5秒后的程序实例：

#!/bin/bash

# Start an infinite loop.
# Use ^C to abort.
while :; do

  # Launch the program in the background.
  /path/to/your/program &

  # Wait 5 seconds, then kill the program (if still alive).
  sleep 5 && { kill $! && wait $!; } 2>/dev/null

done

如果您的命令是交互式：

如果您的命令必须在前台运行以允许用户交互，则需要做更多工作：然后它是在必须在后台运行5秒后终止程序的命令：

#!/bin/bash

# Turn on job control, so we can bring a background job back to the
# foreground with `fg`.
set -m

# Start an infinite loop.
# CAVEAT: The only way to exit this loop is to kill the current shell.
#         Setting up an INT (^C) trap doesn't help.
while :; do

  # Launch program in background *initially*, so we can reliably
  # determine its PID.
  # Note: The command line being set to the bakground is invariably printed 
  #       to stderr. I don't know how to suppress it (the usual tricks
  #       involving subshells and group commands do not work).
  /path/to/your/program &
  pid=$!   # Save the PID of the background job.

  # Launch the kill-after-5-seconds command in the background.
  # Note: A status message is invariably printed to stderr when the
  #       command is killed. I don't know how to suppress it (the usual tricks
  #       involving subshells and group commands do not work).
  { (sleep 5 && kill $pid &) } 2>/dev/null 

  # Bring the program back to the foreground, where you can interact with it.
  # Execution blocks until the program terminates - whether by itself or
  # by the background kill command.
  fg

done

Answer 2

查看watch命令。它将让您重复监视输出运行程序。如果你需要在5秒后手动杀死该程序，可能需要有点花哨。

https://linux.die.net/man/1/watch

一个简单的例子：

watch -n 5 foo.sh

Answer 3

直接回答你的问题：

在睡眠中运行10次5：

#!/bin/bash 
COUNTER=0
while [ $COUNTER -lt 10 ]; do
    # your script
    sleep 5
    let COUNTER=COUNTER+1 
done

持续跑步：

#!/bin/bash 
while [ 1 ]; do
    # your script
    sleep 5
done

Answer 4

如果代码上没有输入，您只需执行

即可

#!/bin/bash

while [ 1 ]
do
    ./exec_name

    if [ $? == 0 ]
    then
        sleep 5
    fi
done