Say I want to read multi-line user input, do something with it, then read some more. I try, 

#!/usr/bin/perl
use strict;

my $input;

local $/;
$input = <STDIN>;
print $input;

$input = <STDIN>;
print $input;

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It receives user input the first time, but prints and exits the script without letting me receive user input the second time. I tried undefining $/ in a separate block, and just seeing if I could read single line input the second time, but it does the same thing - just does the first read, then exits: 

#!/usr/bin/perl
use strict;

my $input;
{
local $/;
$input = <STDIN>;
}
print $input;

$input = <STDIN>;
print $input;

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this doesn't work either: 

#!/usr/bin/perl
use strict;

my $holdRS = $/;
local $/;
my $input = <STDIN>;
$/ = $holdRS;

print $input;

my $holdRS = $/;
local $/;
my $input2 = <STDIN>;
$/ = $holdRS;

print $input2;

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This works though: 

#!/usr/bin/perl
use strict;

my @userinput = <STDIN>;
foreach (@userinput) { print; }

my @userinput = <STDIN>;
foreach (@userinput) { print; }

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What is it about undefining $/ that allows me to read user input only one time? (even if I set it back to default first)

In reply to how to read STDIN interactively by Allasso

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