使用ARGF在Ruby脚本中陷阱Ctrl-D [英] Trap Ctrl-D in a Ruby Script with ARGF

问题描述

我当前正在使用ARGV.gets从命令行捕获用户输入.我想允许Ctrl-D终止脚本，但不知道如何使用Signal.trap或通过错误处理来执行此操作.我试图找到诸如Ctrl-D之类的陷阱代码列表，但是找不到我想要的东西.同样，营救Exception也不起作用，因为Ctrl-D不会引发异常.是否有Ctrl-D陷阱代码或其他任何方法可以检测到该错误?

I am currently using ARGV.gets to capture user input from the command line. I want to allow Ctrl-D terminate the script, but don't know how to do this using Signal.trap or through error handling. I tried to find a list of trap codes for something like Ctrl-D but was unable to find anything I was looking for. Likewise, rescuing Exception doesn't work because Ctrl-D doesn't raise an exception. Is there a trap code for Ctrl-D or any other way to detect this?

例如... 我目前能够通过捕获...来检测Ctrl-C ...

For example... I am currently able to detect Ctrl-C by trapping...

# Trap ^C 
Signal.trap("INT") { 
   # Do something 
   exit
}

或错误处理...

def get_input
   input = ARGF.gets
   input.strip!
   rescue SystemExit, Interrupt => e
   # If we get here, Ctrl-C was encountered
end

但是，我无法捕获或检测Ctrl-D.

However, I haven't been able to trap or detect Ctrl-D.

推荐答案

ARGF仅在流的一种特殊情况下. Ctrl + D只是输入的结尾.

ARGF in just a special case of stream. Ctrl + D is just end of input.

请牢记使用方法ARGF.eof?. 链接到文档

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