You never created or assigned anything to @Text.
( oh, that error is cause you're missing a semicolon at the end of the use statement. ) 

use Text::Wrap qw( wrap );

my $file_name = "C:\\ACK_DATA\\ar835.dat";

open(my $fh, $file_name)
   or die "Unable to open input file \"$file_name\": $!\n";

$Text::Wrap::columns = 80;
while (<$fh>) {
   print wrap('', '', $_);
}

[download]

Updated to fix error mentioned in reply.

In reply to Re^5: 80 characters long by ikegami
in thread 80 characters long by aixmike

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