What have you tried? Do you know how to open a file and read from it - see open if not?

Checking for more than 1 line should be as simple as reading two lines and checking that you got the second (for an empty file you don't get the first either, but for your purpose you can ignore than and just take note of success with the second read).

When you have some code to show report back for comment.

perldoc -q count

The special variable $. gives you the current line number for most recently used file handle. So, if you are reading a file, $. will tell you how lines in to the file you have read.

use strict;
use warnings;
use File::Slurp;

my @array = read_file("filename");

my $lines = @array;

if ( $lines == 1 ) {
    print "total amount of lines are 1";
}
else {
    print "file has $lines lines";
}
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That requires reading the whole file. For small files that's not a problem, but as a general thing you should only read as much at a time as you need. For that reason for loops and other techniques that read all the lines of a file into a list or array should be avoided unless you actually need random access to the whole file.

Perl is the programming world's equivalent of English

What about something like this? lol

use strict;
use warnings;

open my $file, '<', "filename";

my $count_lines;

my @array;

while (<$file>) {
    $count_lines++;
    push @array, qw($_);
    last if ( $count_lines == 2 );
}

my $lines = @array;
print $lines;

if ( $lines == 1 ) {
    print "this file only has 1 line";
}
else {
    print "this file has 2 or more lines";
}
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Take a look at Count number of lines in a text file.

Update: my 2 cents...

use strict;
use warnings;
use IO::All;

my $file = shift || die $!;
my $io = io $file; 

print qq(I think it's more than one!\n) if $io->[1];
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Note: "IO::All file used as an array reference becomes tied using Tie::File".

Regards, Karl

perl -e 'my $c = <> for 1..2; print "One line\n" if $. == 1;' file.txt
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