If I have a program called foo that does something like:

Hello world. Should I continue? (y/n)
(and here the user must type 'y' and hit Enter before continuing)
Thanks!

then how would I write a perl script that launches foo, waits until it sees the line "Hello world. Should I continue? (y/n)", and automatically enters the "y" response, all while printing to stdout the output that foo is printing and the responses that the perl script is entering? Actually, how can I do it without downloading and installing any additional perl modules that don't come with the standard perl distribution? (Even if there is a specialized class that does it more elegantly, can I just do it with normal reads and writes?)

I know this must be simple, and I tried to figure it out myself, but I couldn't find any phrase to Google for that would give me the answer (e.g. "perl automate entering input", etc.)

Is it just two lines of code? I know asking people to write code for you is frowned upon, but in this case wouldn't it be faster than typing a response in English sentences? :)

In reply to perl code to automate launching a program and entering responses by bennetthaselton

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