# Declaring SPI function prototypes

The service header file, xxxspi.h, contains the function prototype for each SPI function.

The signature of an SPI function is typically almost identical to that of its associated API function, except the SPI function contains an additional parameter to indicate the invoker of the SPI function. This value may be a service ID (if the SPI function is called by another service) or CTA_APP_SVCID (if the SPI function is called by an API function).

tik service

<<<< excerpt from tikspi.h >>>>

/*----------------------------------------------------------
SPI function for tikStartTimer API.
----------------------------------------------------------*/
DWORD NMSAPI tikSpiCmdStartTimer( CTAHD ctahd,
TIK_START_PARMS *start,
WORD source) ;