The network library is accompanied by a C header file that is reproduced below (with some deliberate errors). You also get a fully working application (Net Sync) that uses the library. Net Sync is provided as a Metrowerks CodeWarrior project.

/*************************************************************************
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***************************************************************************
// PE_NetLib.h

#pragma mark ***** Error Codes
// Error Codes
#define PE_ErrorClass		0x9000
#define PE_ErrNone		errNone			// Zero
#define PE_ErrParameter		(PE_ErrorClass | 1) 	// Invalid parameter passed to function
#define PE_ErrOSIncompatible	(PE_ErrorClass | 2)	// Wrong OS version (only 3.3 and higher)
#define PE_ErrDatabaseReadWrite	(PE_ErrorClass | 3)	// Error reading / writing to network service
#define PE_ErrNoSuchRecord	(PE_ErrorClass | 4)	// Specified record doesn't exist
#define PE_ErrNoMemory		(PE_ErrorClass | 5) 	// Insufficient memory

#pragma mark ***** Defines
// Defines
#define PE_NEW_RECORD		dmMaxRecordIndex	// Create a new record
#define PE_SERVICE_NAME_LEN	32			// Max length of network service name
#define PE_CONN_NAME_LEN	22			// Max length of connection name


#pragma mark ***** Structures
// Structures
typedef struct PE_ServiceListType
{
	Char service[PE_SERVICE_NAME_LEN];	// name of service
	Char connection[PE_CONN_NAME_LEN];	// name of connection the service uses
	UInt16 recordNum;			// the record number of the service
} PE_ServiceListType;

typedef struct PE_ServicePreferencesType
{
	UInt32 interface;			// 'slip', 'ppp-' or 'loop'
	UInt32 ipAddr;				// IP address if static
	UInt32 primaryDNS;			// Primary DNS server if static
	UInt32 secondaryDNS;			// Secondary DNS server if static
	UInt32 closeWaitTime;			// Wait before closing connection after NetLibClose
	UInt16 inactivityTimer;			// Wait before closing connection due to inactivity
	UInt16 establishmentTimeout;		// Time before giving up on connection establishment
	UInt8 reserved;				// Not used
	UInt8 reserved2:6;			// Not used
	UInt8 useVJCompression:1;		// Use VJ header compression
	UInt8 useModem:1;			// Use modem (phone number) to connect
	MemHandle serviceNameH;			// Name of the service
	MemHandle usernameH;			// Username
	MemHandle passwordH;			// Password
	MemHandle loginScriptH;			// Login script (each line is NULL terminated)
	MemHandle connectionH;			// Connection to use (from connection database)
} PE_ServicePreferencesType;


typedef struct PE_PhonePreferencesType
{
	UInt16 reserved: 12;			// reserved
	UInt16 dialPrefixEnabled:1;		// dial prefix string provided
	UInt16 callWaitingEnabled:1;		// call waiting string provided
	UInt16 callingCardEnabled:1;		// calling card string provided
	UInt16 pulseDial:1;			// pulse dial or touch-tone
	MemHandle phoneNoH;			// phone number
	MemHandle prefixH;			// dial prefix
	MemHandle callWaitingH;			// call waiting string
	MemHandle callingCardH;			// calling card number string
} PE_PhonePreferencesType;


#pragma mark ***** Functions
// Functions

// Function: PE_GetLibraryVersion
// Returns the library version number
//
// Parameters IN:
// none
//
// Parameters OUT:
// none
//
// RETURNS:
// Returns the library version number
const Char *PE_GetLibraryVersion();


// Function: PE_GetActiveService
// Gets the record number of the currently active service.  The active service is the service
// used whenever NetLibOpen is called.
//
// Parameters IN:
// none
//
// Parameters OUT:
// none
//
// RETURNS:
// The record number of the currently active service.  If the record is not found then the first
// record (0) is returned.
UInt16 PE_GetActiveService();


// Function: PE_SetActiveService
// Sets the active service to be the service specified
//
// Parameters IN:
// recordNum - record number of service that should be made the active service
//
// Parameters OUT:
// none
//
// RETURNS:
// PE_ErrNone - no error
// PE_ErrOSIncompatible - wrong Palm OS version
// PE_ErrDatabaseReadWrite - error writing to network service database
// PE_ErrNoSuchRecord - the specified record was not found
Err PE_SetActiveService(UInt16 recordNum);


// Function: PE_GetRecordIDFromNumber
// Converts a service record number into a unique service ID
//
// Parameters IN:
// recordNum - record number to convert
//
// Parameters OUT:
// none
//
// RETURNS:
// The record ID corresponding to the given record number.  If the record is not found then
// zero is returned.
UInt32 PE_GetRecordIDFromNumber(UInt16 recordNum);


// Function: PE_GetServiceList
// Gets a list of all the network services in the network database.  An array of services
// it created.  The developer is responsible for freeing this list (call MemPtrFree)
//
// Parameters IN:
// none
//
// Parameters OUT:
// numOfServices - number of services in the network database
// serviceList   - an array of these services, the connection they use and the record number
//
// RETURNS:
// PE_ErrNone - no error
// PE_ErrParameter - serviceList is already allocated
// PE_ErrOSIncompatible - wrong Palm OS version
// PE_ErrDatabaseReadWrite - error writing to network service database
// PE_ErrNoMemory - unable to allocate memory for the list
//
// Note: Don't forget to call MemPtrFree to free the memory used by the list
Err PE_GetServiceList(UInt16 *numOfServices, PE_ServiceListType **serviceList);


// Function: PE_SaveService
// Saves the service into the network service database
//
// Parameters IN:
// recordNum  - record number of service to change or PE_NEW_RECORD if a new
//              record should be created
// service    - new or modified network service record
// phone      - new or modified phone record
//
// Parameters OUT:
// newRecord  - the new record number for the service.  This will typically be the same
//              as recordNum, except if the record is a new record or the service
//              name has changed (the service database is sorted into alphabetical order)
//
// RETURNS:
// PE_ErrNone - no error
// PE_ErrParameter - service or phone not provided
// PE_ErrOSIncompatible - wrong Palm OS version
// PE_ErrDatabaseReadWrite - error writing to network service database
// PE_ErrNoSuchRecord - invalid record specified
Err PE_SaveService(UInt16 recordNum, UInt16 *newRecord, PE_ServicePreferencesType *service, \
			PE_PhonePreferencesType *phone);


// Function: PE_LoadService
// Loads the service from the network service database.  When the data is no longer needed
// you should call PE_FreeService, which will free the string handles used by the record.
//
// Parameters IN:
// recordNum  - record number of the service to be retrieved
//
// Parameters OUT:
// service    - service record is populated from network database
// phone      - phone record is populated from network database
//
// RETURNS:
// PE_ErrNone - no error
// PE_ErrParameter - service or phone not provided
// PE_ErrOSIncompatible - wrong Palm OS version
// PE_ErrDatabaseReadWrite - error writing to network service database
// PE_ErrNoSuchRecord - invalid record specified
//
// Note: Don't forget to call PE_FreeService to free the allocated memory
Err PE_LoadService(UInt16 recordNum, PE_ServicePreferencesType *service, \
			PE_PhonePreferencesType *phone);


// Function: PE_FreeService
// Frees the string handles used for network and phone services
//
// Parameters IN:
// service    - service record populated by prior PE_LoadService call
// phone      - phone record populated by prior PE_LoadService call
//
// Parameters OUT:
// none
//
// RETURNS:
// PE_ErrNone - no error
// PE_ErrParameter - service or phone not provided
// PE_ErrOSIncompatible - wrong Palm OS version
Err PE_FreeService(PE_ServicePreferencesType *service, PE_PhonePreferencesType *phone);