How to call a script interactively from perl

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

Hi, i am newbie to perl and coded a small perl program with the below objective as follows:

1. Triggering another script(ThirlPartyScript.start) from this perl.
2. Directing the output of that script in a file such that only those lines are stored which match a string.
3. Mail the file generated at the step 2.

I am able to achieve the above objectives on a test script. But ThirlPartyScript.start after completion expect some inputs and hence user interaction, so when i call this script from my perl code, it never completes as it seems to be waiting for that user interaction to complete. below is the code i am using to execute that third party script:

#Run the command    
open( CMD, "$run_cmd|" ) || die "Not able to run \"$run_cmd\":$!\n"; 
    while( <CMD> ){      # read command's output from the pipe
         # do write to file with what we read back from the proces
        print $fh_cmd_in $_;
      
    }
[download]

Can someone let me know how to supply that iterative argument when calling a script from perl so that the called script completes? Thanks

Comment on How to call a script interactively from perl Download Code

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Re: How to call a script interactively from perl by BrowserUk (Patriarch) on Oct 08, 2012 at 22:07 UTC
If the script is a purely command line program that takes its inputs from stdin, you can avoid IPC::open3 by feeding the required interactions to via a pipe. Say the script requires two lines of input, like this one: `#! perl -slw use strict; chomp( my $interact1 = <STDIN> ); chomp( my $interact2 = <STDIN> ); print "Got: $interact1 $interact2";` [download] Then you can feed it the required inputs and retrieve its output like this: `C:\test>perl -E"$p = open I, '-\|', '( echo fred & echo jim ) \| interac +t.pl'; say for <I>;" Got: fred jim` [download] This often will not work for programs that expect passwords. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. RIP Neil Armstrong	[reply] [d/l] [select]
Re: How to call a script interactively from perl by zentara (Archbishop) on Oct 09, 2012 at 12:09 UTC
Here is a simple usage of IPC::Open3 showing how to write to your STDIN. `#!/usr/bin/perl use warnings; use strict; use IPC::Open3; #interface to "units" calculator #my $pid = open3(\WRITE, \READ, \ERROR,"units -t"); #terse output my $pid = open3(\WRITE, \READ, 0 , "units -t"); #if \ERROR is set to 0, STDERR is sent to STDOUT #chomp(my $prompt = <READ>); #print "$prompt\n"; foreach ( '100 yards', '1 mile', '1 kilometer', '1 parsec', '1 foobar' +){ print WRITE "$_\n meters \n"; chomp(my $answer = <READ>); print "$_ = $answer meters\n"; } __END__` [download] I'm not really a human, but I play one on earth. Old Perl Programmer Haiku ................... flash japh	[reply] [d/l]
Re^2: How to call a script interactively from perl by LetMeAsk (Initiate) on Oct 15, 2012 at 21:14 UTC
Thanks all for the answers, let me detail the situation again, The third party script after completion (first round) ask a question: `Select Option :` [download] Manually if i supply an "X" then it quits the script but as i am calling this third party script from my perl script i want perl to terminate that script so that the output of the thirdpartyscript can be written to a file(by perl) and so that i can use that file. Sorry if you replied to the exact scenario. Thanks	[reply] [d/l]
Re^3: How to call a script interactively from perl by zentara (Archbishop) on Oct 16, 2012 at 11:07 UTC
You have me confused. How can you terminate the script in a way that allows it to output to a file? You need to describe in exact detail how this third party script runs. Maybe you are looking to put the process in the background, i.e. a background process? I'm not really a human, but I play one on earth. Old Perl Programmer Haiku ................... flash japh	[reply]
Re^4: How to call a script interactively from perl by LetMeAsk (Initiate) on Oct 16, 2012 at 14:34 UTC
Re^5: How to call a script interactively from perl by McA (Priest) on Oct 16, 2012 at 14:44 UTC
Some notes below your chosen depth have not been shown here
Re: How to call a script interactively from perl by Illuminatus (Curate) on Oct 08, 2012 at 21:21 UTC
You want Open3. This assumes you know what you need to write to the third-party script to get it to exit gracefully fnord	[reply]


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