Thank you for all your gentle answers, but if I run this: 
#!/usr/bin/perl
print "Content-type: text/html\n\n";
srand();
$fil="ch";
open(OUT, '>>'.$fil);
for($i=1;$i<10001;$i++){
 $j=int(rand(20000))+440000;
 $k=substr(pack('l>',$j),1);
 print OUT $k;
}
close(OUT);
print "DONE !";

[download]
it produces one file with a variable length, but always greater than 30000 characters (for exemple 30045) ! So I suppose something is wrong in the pack line coding...

In reply to Re^3: 3-byte representation by Anonymous Monk
in thread 3-byte representation by gerleu

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