perlintro, included with Perl, will enlighten the path amid the darkness. Let thy future searches begin in the canon of Perl's documentation.

In particular, "Files and I/O".

Spend 30 minutes with perldoc perlintro.

Hi Chris202 and welcome to the monastery.

You can use an open command very similar to the one that already exists in your program, except switching the less-than to a greater-than symbol to indicate output. Then use the Perl select command to indicate that you want print output to go there instead of STDOUT (which is usually the console).

use strict;
use warnings;

open (my $output, '>', 'output.txt') or die "cannot open > output.txt 
+$!";
select $output;

open (my $file, '<', 'file.txt') or die "cannot open < file.txt $!";
while (<$file>) {
    print unless (/^A/)
}

select *STDOUT;
print "All Done.\n";
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The print unless ... idiom in the example above is a more terse way to write the same thing you had in your program.

...What I want is just to get these results to be saved in a new text file. ..
That can easily be done by printing your desired output to a file filehandle, you have opened like so:

use strict;
use warnings;

# please note the 'sign' ">"
open( my $fh, ">", "output_file.txt" ) or die "cannot open output_file
+.
+txt$!";
open( my $file, "<", "/file.txt" ) or die "cannot open < file.txt $!";
while (<$file>) {
    unless (/^A/) {

        # please note "$fh" filehandle to write to
        print $fh $_;
    }
}
close $file or die $!;
close $fh   or die $!;
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$ perl your_script.pl > report.txt
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perl -ne "print unless/^A/;" file.txt > newfile.txt
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In Unix it is probably more like:

perl -ne 'print unless/^A/;' ./file.txt > ./newfile.txt
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