Re: Reading and unpacking on one line

#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11123425
use warnings;

open FILNAM, '<', \<<END or die $!;
1234567890
abcdefghijkl
END

my $val = unpack 'H32', do { local $/ = \16; <FILNAM> };

print "$val\n";
[download]

UPDATED: changed input to an in memory file to make program completely self contained.

Comment on Re: Reading and unpacking on one line Download Code

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Re^2: Reading and unpacking on one line by Anonymous Monk on Nov 05, 2020 at 22:18 UTC
Thanks to all for the answers. I understand what happened now. :) I will ask you this, since you slightly changed the method used to read the data (not that I need to know for this particular case, but just want to increase my understanding in general) - how do I specify reading 16 characters (perhaps UTF-8, for example) versus reading 16 bytes (as in pure binary data? Thank you again	[reply]
Re^3: Reading and unpacking on one line by choroba (Archbishop) on Nov 05, 2020 at 22:33 UTC
The behaviour depends on the filehandle. It's documented at the end of read > depending on the status of the filehandle, either (8-bit) bytes or characters are read. Similarly, sysread: > Note that if the filehandle has been marked as ":utf8", Unicode characters are read instead of bytes So, to read UTF-8, open the file handle with the `:encoding(UTF-8)` layer. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]
Re^3: Reading and unpacking on one line by tybalt89 (Prior) on Nov 05, 2020 at 22:20 UTC
I don't do UTF. Maybe someone else will answer this.	[reply]


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