If I want to execute a program and read the output which is stored in $output, I run it like this: 
my $output = `command <<EOF;
yes
EOF`;

# print output from `command` after giving it 'yes' as input
print $output . "\n";

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If I want to write to a command using a filehandle and not see the resulting output I do this: 
open(COMMAND, '| command') or die("Can't run command: $!\n");

#  give program 'yes' as input
print COMMAND 'yes';

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But what do I do if I want to write to the command as easily as using a file handle and read whatever comes back as easily as a scalar? Essentially I want to do both of the examples above at the same time.

So I'd like to know how to:
1. Run the command
2. See what comes back and read it from $output
3. Make some decisions and print back to filehandle COMMAND
4. Make some more decisoins
5. Print back to COMMAND
6. etc...

In reply to Interactively Read / Write to Program by awohld

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