Perl:

           my (%record) = ();

           $record{'id'}   = 419;
           $record{'time'} = time();
           $record{'name'} = "Quentin";

   C:

           struct record
           {
                int    id;
                time_t time;
                char   name[8];
           } a_record;

           a_record.id   = 419;
           a_record.time = time();
           strcpy (a_record.name, "Quentin");

##</code><code>##

     my (%record) = ();
     my ($packed_record);
     my ($packed_record_size) = 4+4+8;

     # Open the file and read a single record out of it.
     open (FILE, "$data_file");
     read (FILE, $packed_record, $packed_record_size);
     close (FILE);

     # Unpack the record to decode it
     ($record{'id'},$record{'time'},$record{'name'})
         = unpack ("lla8", $packed_record);

     # Make a change
     $record{time} = time;

     $packed_record = pack ("lla8", $record{'id'},$record{'time'},$record{'name'});

     open (FILE, ">$data_file");
     print $packed_record;
     close (FILE);

##</code><code>##

      'Q' 'u' 'e' 'n' 't' 'i' 'n' \x00