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Chapter 2 - Slot Manager / Slot Manager Reference

Slot Manager Routines / Finding sResources

SNextTypeSRsrc

You can use the SNextTypeSRsrc function to step through sResources of one type.

FUNCTION SNextTypeSRsrc (spBlkPtr: SpBlockPtr): OSErr;

spBlkPtr

A pointer to a Slot Manager parameter block.

<--	spsPointer	Ptr	A pointer to an sResource (described in "The sResource," beginning on page 2-7).
<--	spRefNum	Integer	The slot resource table reference number.
<-->	spCategory	Integer	The Category field of the sRsrcType entry (described on page 2-10).
<-->	spCType	Integer	The cType field of the sRsrcType entry.
<-->	spDrvrSW	Integer	The DrSW field of the sRsrcType entry.
<-->	spDrvrHW	Integer	The DrHW field of the sRsrcType entry.
-->	spTBMask	SignedByte	The type bit mask for sRsrcType fields.
<-->	spSlot	SignedByte	The slot number.
<-->	spId	SignedByte	The sResource ID.
<-->	spExtDev	SignedByte	The external device identifier.
<--	spHWDev	SignedByte	The hardware device identifier.

DESCRIPTION

The SNextTypeSRsrc function allows you to find the next sResource, as does the SNextSRsrc function, but the SNextTypeSRsrc function skips disabled sResources.

You indicate the sResource you want returned by identifying the slot number, sResource ID, and device ID in the spSlot, spID, and spExtDev fields of the Slot Manager parameter block you point to in the spBlkPtr parameter. You specify the type of the sResource with the spCategory, spCType, spDrvrSW, and spDrvrHW fields. You must also use the spTBMask to specify which of these sRsrcType entry fields should not be included in the search:

• Set bit 0 to ignore the DrHW field.
• Set bit 1 to ignore the DrSW field.
• Set bit 2 to ignore the cType field.
• Set bit 3 to ignore the Category field.

The SNextTypeSRsrc function returns values in the spSlot, spID, and spExtDev fields corresponding to the sResource that it found.

The SNextTypeSRsrc function also returns a pointer to the sResource in the spsPointer field and returns other information about the sResource in the spIOReserved, spRefNum, spCategory, spCType, spDrvrSW, and spDrvrHW fields.

ASSEMBLY-LANGUAGE INFORMATION

The trap macro and routine selector for the SNextTypeSRsrc function are

Trap macro	Selector
_SlotManager	$0015

You must set up register D0 with the routine selector and register A0 with the address of the Slot Manager parameter block. When _SlotManager returns, register D0 contains the result code.

Registers on entry
A0	Address of the parameter block
D0	$0015

Registers on exit
D0	Result code

RESULT CODES

noErr	0	No error
smNoMoresRsrcs	-344	Requested sResource not found

SEE ALSO

For information on enabling and disabling sResources, see "Enabling and Disabling sResources" on page 2-18 and the description of the SetSRsrcState function on page 2-51.