在ruby中运行脚本时等待键击

Is there a way to run a ruby script and while executing commands in the script ,still respond to key stroke ?

有没有办法运行ruby脚本并在脚本中执行命令时仍然响应键击?

I want to run a ruby script but be able to press "Space" and pause the script (after currently running command executes ), and then press "Space" again and resume the script .

我想运行ruby脚本,但能够按“Space”并暂停脚本(在当前运行命令执行后),然后再次按“Space”并恢复脚本。

My only idea (and im sure its a weird one) , is to open a new thread and wait for key strokes there , then when ill get a key stroke , set a stop_flag. Only now it looks like i need to be checking this flag after each command to know when to stop.

我唯一的想法(并且我确定它是一个奇怪的想法),是打开一个新线程并等待那里的击键,然后当生病得到一个击键时,设置一个stop_flag。只是现在它看起来我需要在每个命令后检查此标志以知道何时停止。

3 个解决方案

#1

You can use a signal to turn debug output on and off at will, if you have a logger set up with appropriate code sprinkled throughout your script:

如果您在整个脚本中设置了适当的代码,则可以使用信号随意打开和关闭调试输出:

 pid = fork do

  # set up a logger
  require 'logger'
  log = Logger.new(STDOUT)
  log.level = Logger::INFO

  # toggle between INFO and DEBUG log levels on SIGUSR1
  trap(:SIGUSR1) do
    if log.level == Logger::DEBUG
      log.level = Logger::INFO
    else
      log.level = Logger::DEBUG
    end
  end

  # Main loop - increment a counter and occasionally print progress
  # as INFO level.  DEBUG level prints progress at every iteration.
  counter = 0
  loop do
    counter += 1
    exit if counter > 100
    log.debug "Counter is #{counter}"
    log.info "Counter is #{counter}" if counter % 10 == 0
    sleep 0.1
  end

end

# This makes sure that the signal sender process exits when the
# child process exits - only needed here to make the example
# terminate nicely.
trap(:SIGCLD) do
  exit(0) if Process.wait(-1, Process::WNOHANG) == pid
end

# This is an example of sending a signal to another process.
# Any process may signal another by pid.
# This example uses a forking parent-child model because this
# approach conveniently yields the child pid to the parent.
loop do
  puts "Press ENTER to send SIGUSR1 to child"
  STDIN.gets
  Process.kill :SIGUSR1, pid
end

The forking and SIGCLD trapping is to make the example fit into one file; any process may send a signal to another.

分叉和SIGCLD陷阱是使示例适合一个文件;任何进程都可以向另一个进程发送信号。

The code inside the fork block is your script. The script sets up a logger with a default log level of INFO, and a handler for the SIGUSR1 signal that toggles the logger between DEBUG and INFO levels.

fork块中的代码是您的脚本。该脚本设置一个记录器,其默认日志级别为INFO,以及一个SIGUSR1信号处理程序,用于在DEBUG和INFO级别之间切换记录器。

The stuff outside of the fork block is just an example of sending a signal to another process. Pressing ENTER will send the signal and alter the logging level of the other process.

fork块之外的东西只是向另一个进程发送信号的一个例子。按ENTER将发送信号并更改其他进程的日志记录级别。

This works on POSIX systems, I have no idea about Windows.

这适用于POSIX系统,我不知道Windows。

#2

Similar idea to @Catnapper, I thought I'd share it although he beat me to the punch.

与@Catnapper类似的想法,我以为我会分享它虽然他打败了我。

require 'io/console' # Ruby 1.9

# Wait for the spacebar key to be pressed
def wait_for_spacebar
   sleep 1 while $stdin.getch != " "
end

# Fork a process that waits for the spacebar 
# to be pressed. When pressed, send a signal 
# to the main process.
def fork_new_waiter
   Process.fork do
      wait_for_spacebar
      Process.kill("USR1", Process.ppid)
   end
end

# Wait for a signal from the forked process
Signal.trap("USR1") do
   wait_for_spacebar

   # Debug code here

   fork_new_waiter
end

# Traps SIGINT so the program terminates nicely
Signal.trap("INT") do
   exit
end

fork_new_waiter

# Run program here in place of this loop
i = 0
loop do
   print i+=1
   sleep 1
end

#3

You can use a system command.

您可以使用系统命令。

In Windows use: system "pause>null"

在Windows中使用:系统“pause> null”

This would be different for each OS. So, you could set a variable to check the OS. Then use the appropriate command. If you want to see if the OS is Windows, your code would look like this:

对于每个OS,这将是不同的。因此,您可以设置变量来检查操作系统。然后使用适当的命令。如果您想查看操作系统是否为Windows,您的代码将如下所示:

#1