I am trying to convert a numbers in a file I have a line: $line2 = printf ("%#x", $line); $line for example is 55473 $line2 ends up containing a 1 not the 0xd8b1 I was expecting and when I run program I see the 0xd8b1 written to the screen, how do I get $line2 to have the 0xd8b1 value ?

Thanks a million to all for the sprintf answer and the other comments.

Getting printf to work was harder than sprintf, however was very educational.

I looked at Prototypes in perlsub and Far More than Everything You've Ever Wanted to Know about Prototypes in Perl -- by Tom Christiansen, I also looked at "perl in a nutshell" and "Perl 5 by Example" and didn't see what to do. Finally after a number of changes and web searches the following seems to work without the warnings " called too early to check prototype at convert4.pl and "use of unitialized value". I am assuming this is correctly coded?

documentation on prototypes is poor for a beginner (or at least me). 

#!/usr/bin/perl
# convert4.pl
use warnings;
use strict;
use Carp ();
local $SIG{__WARN__} = \&Carp::cluck;

     sub capture_stdout($)
    {
        my($v);
        my $line = shift;
        local *STDOUT;
      open(STDOUT, '>', \$v);
        printf ("%#x", $line);
        return $v;
    }

open(MYINPUTFILE, "<test.dat");
open(MYOUTPUTFILE, ">hex.dat");

while(<MYINPUTFILE>)
 {
 my($line) = $_;
 my $line2 ;
 chomp($line);
 $line2 = capture_stdout($line) ;
 print MYOUTPUTFILE "$line2\n";
 }


close(MYINPUTFILE);
close(MYOUTPUTFILE);

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In reply to getting wrong value by ggrise

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