How to give input to terminal (command window) in perl

tsathish123 has asked for the wisdom of the Perl Monks concerning the following question:

Below is my question

I start the process in Linux. Give input through terminal or command window to the process to do different set of actions.

I would like to automate the same by using perl script.

Like start the particular process. After process started, I would like to give input to the process like i give through keyboard to terminal.

Since i am a beginner to perl language. Please help me by giving ideas or example code snippet.

Comment on How to give input to terminal (command window) in perl

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Re: How to give input to terminal (command window) in perl by Discipulus (Canon) on Aug 25, 2016 at 06:55 UTC
Hello and welcome to the monastery tsathish123 as said Expect (Edit: and Test::Expect too) can be an option. Wath you want is generally called IPC (Inter Process Communication) ad the Perl way is described in the language reference found here: perlipc While two core modules can accomplish your task ( IPC::Open2 and IPC::Open3 which also manage `STDERR` ) on CPAN exist many other options, sometimes more viable like IPC::Run IPC::Run3 or if you just need to read from external program also Capture::Tiny The old but always recomandable book `Perl Cookbook` contains a chapter, the 16th, dedicated to `Process Management and Communication` L* There are no rules, there are no thumbs.. Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.	[reply] [d/l] [select]
Re: How to give input to terminal (command window) in perl by kcott (Archbishop) on Aug 25, 2016 at 06:36 UTC
G'day tsathish123, Welcome to the Monastery. That sounds like a job for Expect, whose abstract reads: "automate interactions with command line programs that expose a text terminal interface" Depending on how much of a "beginner" you are, you might want to read "perlintro -- a brief introduction and overview of Perl" first. Each section of this has multiple links to further details and more advanced topics: follow as required. — Ken	[reply]
Re: How to give input to terminal (command window) in perl by Marshall (Canon) on Aug 25, 2016 at 19:51 UTC
It would be helpful if you explained your situation in some more detail. If there is just a fixed set of stuff that you are going to type into this program without caring what the prompts that it says are, then `program <cmds.txt` will often do the job. You could use Perl to make a shell script that potentially could do what you need. The most complicated version of this is having a Perl program "act like you would act" and respond differently to different prompts. Without more information, I am hesitant to recommend that approach because easier solutions might work for you.	[reply] [d/l]