#!/usr/bin/perl

if ($#ARGV < 1 )
{
    print "substr <infile> <outfile> <offset> <len>\n";
    exit;
}

open ( INFILE, $ARGV[0]) || die "Can't open $ARGV[0]";
open (OUTFILE, ">$ARGV[1]") || die "Can't open $ARGV[1]";

$offset = hex($ARGV[2]);
$len    = hex($ARGV[3]);

read (INFILE, $buf,$offset);
read (INFILE, $buf,$len);
#syswrite(OUTFILE,$buf,$len);

select(OUTFILE);

@sent=unpack("c256",$buf);

for($i=0;$i<$len;$i++)
{
#    print "$sent[$i] "; 

    if( ($i>0) && (($i%16)==0) ){print "\n";}

    if( ($i%8) eq 0){print " "; }

    if(($i%16)==0){
	printf("%02x: ",$i); 
    }


    $val=$sent[$i];
    if($val<0){$val+=0x100;}
    printf("%02x ",$val); 

}