[DGD] Guide to upgrading old snapshots

[Felix A. Croes]

Mudlib preparation:

 - replace MAX_STRING_SIZE by (status()[20])
 - if message_done() does not yet exist in the connection object, add the
   following code:

    int message_done()
    {   
        return 4;	/* value meaningful for kernel library only */
    }

 - if connect_telnet() and connect_binary() in the driver object lack a
   parameter, add one:

    varargs int port

 - if include_file() does not yet exist in the driver object, add the
   following code at the end:

    string include_file(string from, string path)
    {   
	return path_include(from, path);
    }

 - For DGD 1.1, in the entire mudlib, rename all variables and functions
   named `nil'.  This is a keyword in DGD 1.2 and later.
 - In the entire mudlib, rename all variables and functions that are named
   `new'.  This is a keyword in DGD 1.5 and later.  In older versions of
   the kernel library, compile_object() in the auto object has a variable
   named `new'.

Before creating the snapshot, recompile all objects.

Create a snapshot with your current DGD, and restore it with DGD 1.5.8+.
You may have to add a parameter `dump_interval = 3600;' to your config file.

Recompile all objects.

Create a snapshot with DGD 1.5.8+, and restore it with DGD 1.6.4+.

Recompile all objects.

Create the final conversion snapshot with DGD 1.6.4+.

At this point, you can upgrade your mudlib to the most recent version.

Regards,
Felix Croes