The Norton Guide Database File Format

Background

The following text is a rough guide to the file format of a Norton Guide database. The information has been pieced together from other sources and from my investigations while writing Norton Guide readers. It isn't fully complete but it should be enough to get anyone started.

If you are able to fill in any of the blanks please feel free to drop me a line with any information you've got.

Introduction

A Norton Guide database consists of a header followed by a series of encrypted records. There are three record types, each of which have an associated ID:

Record Type	ID
Short Entry	0
Long Entry	1
Menu	2

Encryption

Short, long and menu entries are all encrypted. The encryption is a simple XOR 26 scheme. Example C code to decrypt this is:

unsigned char ng_decrypt( unsigned char b )
{
    return( (unsigned char) ( b ^ 0x1A ) );
}

Compression

The text of short, long and menu entries uses a simple form of run-length encoding for spaces. If, when reading text, you encounter a byte value of 255 you should read the next byte and take that as a count of spaces.

The Header

Field	Size	Notes
Magic Value	short	0x474e is a Norton Guide database, 0x4845 is an Expert Help database.
Unknown	short
Unkknown	short
Menu count	short	Count of the number of main menus.
Title	char[40]	The text is NUL terminated if the length is less than 40 characters.
Credit line 1	char[66]	The text is NUL terminated if the length is less than 66 characters.
Credit line 2	char[66]	The text is NUL terminated if the length is less than 66 characters.
Credit line 3	char[66]	The text is NUL terminated if the length is less than 66 characters.
Credit line 4	char[66]	The text is NUL terminated if the length is less than 66 characters.
Credit line 5	char[66]	The text is NUL terminated if the length is less than 66 characters.

The Short Entry

Field	Size	Notes
ID	short	Value is always 0
Length	short	The length of the record in bytes.
Line Count	short	The count of lines in the entry.
Unknown	short
Parent Line	short	The number of the line in the parent entry that points to this entry.
Parent	long	The file offset of the parent entry.
Menu	short	The number of the menu that points to this entry.
Menu Prompt	short	The number of the menu prompt that points to this entry.
Unkonwn	char[8]
Pointers	long[Line Count]	This is an array of file offsets, each offset points to the entry that each line jumps to.
Lines		Line Count lines of NUL terminated text.

The Long Entry

Field	Size	Notes
ID	short	Value is always 1
Length	short	The length of the record in bytes.
Line Count	short	The count of lines in the entry.
See Also Flag	short	Flag to indicate if there are any see-also items.
Parent Line	short	The number of the line in the parent entry that points here.
Parent	long	The file offset of the parent entry.
Menu	short	The number of the menu that points to this entry.
Menu Prompt	short	The number of the menu prompt that points to this entry.
Previous	long	The file offset of the previous entry.
Next	long	The file offset of the next entry.
Lines		Line Count lines of NUL terminated text.

Plus, if and only if the See Also Flag is not 0...

Field	Size	Notes
See Also Count	short	The count of see also entries.
Pointers	long	An array of file offsets, each offset points to the entry associated with the see also.
See Alsos		See Also Count lines of NUL terminated text.

The Menu Entry

Field	Size	Notes
ID	short	Value is always 2
Length	short	The length of the record in bytes.
Prompt Count	short	The count of the number of prompts in the menu.
Unknown	char[20]
Pointers	long[Prompt Count]	This is an array of file offsets, each offset points to the entry that each menu prompt jumps to.
Unkonwn	char[8*Prompt Count]
Title		The menu's title, a NUL terminated string with a maximum of 40 characters1
Prompts		The menu prompts, Prompt Count NUL terminated strings with a maximum of 50 characters each2

---

1. Although I have found guides with longer titles, so it's a good idea to take this into account. ↩

2. Although I have found guides with longer prompts, so it's a good idea to take this into account. ↩