2.7. Getting User Input At this point,you're probably wondering how to get a value from the keyboard into a Perl program. Here's the simplest way: use the line-input operator,<STDIN>.
Each time you use <STDIN> in a place where a scalar value is expected,Perl reads the next complete text line from standard input (up to the first newline) and uses that string as the value of <STDIN>. Standard input can mean many things; unless you do something uncommon,it means the keyboard of the user who invoked your program (probably you). If there's nothing waiting for <STDIN> to read (typically the case unless you type ahead a complete line),the Perl program will stop and wait for you to enter some characters followed by a newline (return).
The string value of <STDIN> typically has a newline character on the end of it. So,you could do something like this:
$line = <STDIN>;
if ($line eq "/n") {
print "That was just a blank line!/n";
} else {
print "That line of input was: $line";
}
In practice,you don't often want to keep the newline,so you need the chomp operator. |