CODEWITHSUNDEEP
perl
Ishita Shah
Ishita Shah

Reputation: 99

Converting hex to binary in Perl

I want to convert the hex values lying in $1, $2, $3, and $4 to binary and save in an array. I know $1 is only a string, so I tried to convert it to hex before converting to binary, but it doesn't work... Here's my code:

#! usr/bin/perl
use warnings;
use strict;

while(<>)
{
    if(/SIB_DBG/)
    {
        if(/TTRB:\s*([\da-f]+)\s([\da-f]+)\s([\da-f]+)\s([\da-f]+)/ ||
           /ETRB:\s*([\da-f]+)\s([\da-f]+)\s([\da-f]+)\s([\da-f]+)/ ||
           /Command\sETRB\s*([\da-f]+)\s([\da-f]+)\s([\da-f]+)\s([\da-f]+)/ )
        {
            my $one = $1;
            my $two = $2;
            my $three = $3;
            my $four = $4;
            print "$_ $one $two $three $four\n";
            printf("binary :%b\n",$four);
        }
    }
}

My input logfile is like

Aug 31 15:25:53 usb3 kernel: [   78.812034] SIB_DBG TTRB:01000680 00080000 00000008 00030840, PTR: ffff88005ff8b800
Aug 31 15:25:53 usb3 kernel: [   78.815428] SIB_DBG ETRB: 5ff8b850 00000000 01000000 01018001

Also I get an error saying in some of the lines..

Argument "f8891" isn't numeric in printf at script.plx line 21, <> line 6.

Upvotes: 2

Views: 15515

Answers (1)

Sobrique
Sobrique

Reputation: 53478

The problem is there's a difference between a text string and a numeric value.

The latter can be represented as hexidecimal, binary, octal - behind the scenes, the computer is thinking in binary anyway.

A text string though, is a sequence of character codes that represent symbols from a character set.

So to do what you want - you need to convert your 'string' to a numeric value first.

Perl has the hex function to do this for you:

#!/usr/bin/env perl
use strict;
use warnings;

my $string = '5ff8b850'; 
my $value =  hex ( $string );

print "Dec: ",$value,"\n";
printf ( "Hex: %X\n", $value );
printf ( "Binary: %b\n", $value );

Upvotes: 5

Related Questions