Question

I am running Perl script under cygwin which takes input from <STDIN> and process the requests continuously.

#!/usr/bin/perl
print "Enter Input:";
while(<STDIN>) {
    print "Recieved Input: $_";
    print "Enter Input:";
}



    $perl testPerl.pl        
    Enter input:input1
    Recieved input:input1
    Enter input:inpt2
    Recieved input:input2
    Enter input:

Now, I would like the up arrow at the current prompt: “Enter input:” to take the previous inputs i.e “input2″,”input1”

It behaves as expected when running under windows enivronment (cmd.exe)
But the problem under cygwin is that the up arrow literally takes the cursor 1 row up i.e it takes to the line “Recieved input:input2”

Please share your thoughts on this.

Answer 1

Look at the Term::Readline module. This will take over input for your program, and handles history, which is what I think you’re talking about.

This would be a direct translation of your program to using Term::ReadLine:

 use Term::ReadLine;
 my $term = new Term::ReadLine 'Simple Perl calc';
 my $prompt = "Enter Input: ";
 while ( defined ($_ = $term->readline($prompt)) ) {
   print "Recieved Input:$_\n";
   $term->addhistory($_) if /\S/;
 }