Hello, I'm trying to use STDIN first to read from the output of the previous process and then to read from the terminal. According to http://perldoc.perl.org/perlop.html#I%2fO-Operators I should be able to do this:

"The <> symbol will return undef for end-of-file only once. If you call it again after this, it will assume you are processing another @ARGV list, and if you haven't set @ARGV , will read input from STDIN."

That's what I need! My simplified program, called pgm, is the following:

#!/opt/local/tools/bin/perl

    use 5.24.0;
    use strict;
    use warnings;

    my $response;

    unless (-t STDIN)

        {
            while (<STDIN>)

                {
                    chomp;
                    print "input line is $_\n";
                }
        }

    print "Now enter something: ";
    $response = <>;
    print "You entered -->", $response, "<--\n";

[download]

and I invoke it as follows:

echo Hello | pgm

But it doesn't wait for anything to be entered at the <>:

echo Hello | pgm
input line is Hello
Use of uninitialized value $response in print at /userdata/cfor/utils/
+worklib/pgm line 25.
Now enter something: You entered --><--

[download]

Wouldn't the while (<STDIN>) end because it encountered EOF, after which it should then read input from STDIN?

In reply to Unable to reuse STDIN by fireblood

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