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Chapter 2 - Slot Manager / Slot Manager Reference

Slot Manager Routines / Finding sResources

SGetSRsrc

You can use the SGetSRsrc function to find any sResource, even one that has been disabled.

FUNCTION SGetSRsrc (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).
<-->	spParamData	LongInt	On input: parameter flags. On output: 0 if the sResource is enabled or 1 if disabled.
<--	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.
<-->	spSlot	SignedByte	The slot number.
<-->	spId	SignedByte	The sResource ID.
<-->	spExtDev	SignedByte	The external device identifier.
<--	spHWDev	SignedByte	The hardware device identifier.

DESCRIPTION

The SGetSRsrc function allows you to specify whether the function should include disabled sResources, whether it should continue looking for sResources in higher-numbered slots, and whether it should return information about the specified sResource or the one that follows it.

You specify an sResource with the spSlot, spID, and spExtDev fields of the Slot Manager parameter block you point to in the spBlkPtr parameter. You must also include flags in bits 0, 1, and 2 of the spParamData field as follows:

• Set the fAll flag (bit 0) to search both enabled and disabled sResources. Clear this flag to search only enabled sResources.
• Set the fOneSlot flag (bit 1) to search only the specified slot. Clear this flag to search all slots.
• Set the fNext flag (bit 2) to return information about the sResource with the next higher sResource ID than the specified sResource (or the first one on the next card if the fAll flag is set). Clear this flag to return data about the specified sResource.

The SGetSRsrc function returns values in the spSlot, spID, and spExtDev fields corresponding to the sResource that it found. If you cleared the fNext flag, these fields retain the values you specified when calling the function. In addition, the function returns 0 in the spParamData field if the sResource is enabled or 1 if it is disabled. If you cleared the fAll bit, the spParamData field always returns the value 0.

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

SPECIAL CONSIDERATIONS

The SGetSRsrc function is available only with version 1 or later of the Slot Manager. You can use the SVersion function, described on page 2-30, to determine whether the Slot Manager is version 1 or later.

ASSEMBLY-LANGUAGE INFORMATION

The trap macro and routine selector for the SGetSRsrc function are

Trap macro	Selector
_SlotManager	$000B

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	$000B

Registers on exit
D0	Result code

RESULT CODES

noErr	0	No error
smNoMoresRsrcs	-344	Requested sResource not found

SEE ALSO

For more control in finding sResources, you can also use the SGetTypeSRsrc function, described next.