# wrong
while (my $line = $fh){

# right
while (my $line = <$fh >){
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open (my $fh, "<", "test.txt");
my @file_array = (<$fh>);
print @file_array,"\n";
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P.S. Since you are dealing with big files, you might want to use ARGV's special line by line processing magic. That way, you never pull the whole file into memory. Google for perl ARGV magic.

#!/usr/bin/perl
use warnings;
use strict;

# use ARGV's magic
@ARGV = "test.txt";

my @results;

while ( <ARGV> ){
   chomp $_;
    if ($_ =~ m/head/){
        push (@results, $_);
      }
}

print "@results\n";
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Your problem is (potentially) two-fold: with this snippet you are tying to read the entire file into memory (but actually, you are getting stuck in a neverending while loop because you use $fh instead of <$fh>). Are you doing something special with this that requires the entire file to be read in at once or just printing it to STDOUT (or another file handle)? If the latter, a simple fix is:

open my $fh, "<", "Google_1.txt";
print $_ while <$fh>;
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One more thing... If the input file is small enough and you really do want to read it into an array for something other than printing, you can use something like this instead of your while loop:

open my $fh, "<", "Google_1.txt";
my @file_array = <$fh>;
chomp @file_array;
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I used the <$fh> but the line does not get saved in the array? It also does not print anything

Can you show the new code with your changes please?