Re^5: Error binmode() on unopened filehandle

I don't understand the point that you are trying to make. You open a file handle to a Perl var. That's fine. You set binmode before you read from that file handle and that's fine too.

Find some .jpg file you have somewhere and try the code that I posted. Use of the DATA file handle is "special".

Your initial premise that you could read binary data from the DATA file handle is wrong. That data will be in a character format.

Update: Here is a Perl program that reads and prints itself. DATA is an already read and opened file handle.

use warnings;
use strict;

print "testing seek of DATA handle\n";
print "this will print this program\n";
seek (DATA,0,0); 
my $text = do{ local $/ = undef; <DATA>; };
print $text;


__DATA__
asdfasdf asdfasdf
[download]

Comment on Re^5: Error binmode() on unopened filehandle Download Code

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Re^6: Error binmode() on unopened filehandle by jo37 (Curate) on May 03, 2020 at 14:54 UTC
My last example was without the special `DATA` file handle and shows that `my $binary = <$fh>` will read the data from `$fh` up to and including the first appearance of `$/`. Using `binmode` on a file handle does not change this behaviour. You may check if: your data really does not contain a record separator the generated base64 data, when decoded, resembles the original file EDIT: Here is another: `#!/usr/bin/perl use strict; use warnings; use constant RANDFILE => "rand.dat"; system "dd if=/dev/urandom of=" . RANDFILE . " bs=1k count=64"; open my $fh, '<', RANDFILE or die; binmode $fh; my $binary = <$fh>; print "got: ", length($binary), "\n";` [download] Greetings, -jo `$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$`	[reply] [d/l] [select]
Re^6: Error binmode() on unopened filehandle by ikegami (Patriarch) on May 04, 2020 at 03:27 UTC
Your initial premise that you could read binary data from the DATA file handle is wrong. Works for me. `use feature qw( say ); binmode DATA if $ARGV[0]; while (<DATA>) { say sprintf "%v02X", $_; } __DATA__ abc def` [download] `>perl a.pl 0 61.62.63.0A 64.65.66.0A >perl a.pl 1 61.62.63.0D.0A 64.65.66.0D.0A` [download]	[reply] [d/l] [select]