Argument "\0^D&" isn't numeric in sysseek
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Argument "\0^D&" isn't numeric in sysseek

Based on those bytes/octets, to turn them a "number", it all depends on what kind ... see pack, unpack, perlpacktut

Just guessing at the right one (guessing is bad, knowing is better)

use Data::Dump qw/ dd pp /;
dd( unpack q{c*}, "\0^D&"  );# (0, 94, 68, 38)
dd( unpack q{C*}, "\0^D&"  );# (0, 94, 68, 38)
dd( unpack q{W*}, "\0^D&"  );# (0, 94, 68, 38)
dd( unpack q{s*}, "\0^D&"  );# (24064, 9796)
dd( unpack q{S*}, "\0^D&"  );# (24064, 9796)
dd( unpack q{l*}, "\0^D&"  );# 642014720
dd( unpack q{L*}, "\0^D&"  );# 642014720
dd( unpack q{i*}, "\0^D&"  );# 642014720
dd( unpack q{I*}, "\0^D&"  );# 642014720
dd( unpack q{n*}, "\0^D&"  );# (94, 17446)
dd( unpack q{N*}, "\0^D&"  );# 6177830
dd( unpack q{v*}, "\0^D&"  );# (24064, 9796)
dd( unpack q{V*}, "\0^D&"  );# 642014720
dd( unpack q{q*}, "\0^D&"  );# ()
dd( unpack q{Q*}, "\0^D&"  );# ()
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Here is my code so far.

open(my $infile, '<', "./file") or die "Cannot open file: $!";
binmode($infile);

open(my $outfile, '>', "./reference1") or die "Cannot create file: $!"
+;
binmode($outfile);

my $buffer = '';
sysseek $infile, 0x15, 0;
sysread $infile, $buffer, 0x03;
syswrite $outfile, $buffer;
$buffer =~ s/(.)/sprintf("%x",ord($1))/eg; #this converts it into hex.
print  $buffer, "\n"; #this prints the converted $buffer (04C0)
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Maybe I am trying to go about this the wrong way.
$buffer = (04C0)
It would be really nice to be able to use $buffer like this but I dont think its possible that way:

sysseek $infile, $buffer, 1;
sysread $infile, $new, 0x40000;
syswrite $newfile, $new;
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Remember that $buffer contains the 04C0, which is a reference to the actual data further into the file. so I get the reference values with this:

my $buffer = '';
sysseek $infile, 0x15, 0;
sysread $infile, $buffer, 0x03;
syswrite $outfile, $buffer;
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Then I try to sysseek to that position in the file like this, using the reference i obtained with the code above:

sysseek $infile, $buffer, 1;
sysread $infile, $new, 0x40000;
syswrite $newfile, $new;
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Also Anonomous Monk, please let me thank you for the help so far. Im not exactly pro at programming, but I know how i want it to work, I am just having a hard time setting this up to work. I feel like i am going in circles now.

What is $buffer in actuality? use ddumper^{Basic debugging checklist} Basic debugging checklist item 4

What does it represent in terms of bits bytes and endianess (datatype)?

perlpacktut

$buffer stores the reference to where the actual data is in the file.
so it will look like this:

my $buffer = '';
sysseek $file, 0x15, 0;
sysread $file, $buffer, 0x03;
syswrite $outfile, $buffer;
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And 0x15 is the reference to the actual data in this file. this code will get that reference and store it in $buffer.
What I want to be able to do is use $buffer in sysseek like this:

sysseek $file, $buffer, 0;
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as opposed to:

sysseek $file, 0x400, 0;
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