Re: How to call a script interactively from perl

[zentara]

in reply to How to call a script interactively from perl

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__

[LetMeAsk]

Thanks all for the answers, let me detail the situation again, The third party script after completion (first round) ask a question:

Select Option :

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

[zentara]

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?

[LetMeAsk]

I am sorry to confuse you, ok here i go again: There is an existing script (Lets call it ThirdPartyScript and i cannot do any modifications to it) which performs some processing and displays output on the STDOUT and at the end it asks for options. For example, when you provide an option "i" it means include flag and you can specify any search string. It then retrieves the results matching that search string from its database and after displaying those results it again wait for next action with the following prompt:

Select option:

Now, either you can provide next option as i (to include other search string or "d" to delete the listed results etc or "X" to quit script. Now, i am writing a perl script with the intention to run above thirdpartyscript with a specific search string from this perl code and write the result of this run to a unix file. Then again my perl code will email this output file to the interested parties. My perl code works fine when i run that for any other command (e.g. ls), but when i run that for the above third party script, it never completes execution and the output file never populated. So, i thought may be it is because the thirdpartyscript do not exit execution until an "x" is specified as explained above. Please let me know if it helps. Thanks