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Chapter 2 - Slot Manager / Slot Manager Reference

Slot Manager Routines / Finding sResources

SGetTypeSRsrc

You can use the SGetTypeSRsrc function to step through sResources of one type, including disabled ones.

FUNCTION SGetTypeSRsrc (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.
-->	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 SGetTypeSRsrc function allows you to find the next sResource of a certain type, as does the SNextTypeSRsrc function, but the SGetTypeSRsrc function also allows you to find disabled sResources and to limit searching to a single slot.

You specify an sResource with the spSlot, spID, and spExtDev fields of the Slot Manager parameter block you point to in the spBlkPtr parameter, and you specify the type of the sResource with the spCategory, spCType, spDrvrSW, and spDrvrHW fields. You must also use the spTBMask field to specify which of these sRsrcType 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.

You must also set the fAll flag of the spParamData field (bit 0) to search both enabled and disabled sResources or clear this flag to search only enabled ones. Set the fOneSlot flag (bit 1) to search only the specified slot, or clear this flag to search all slots. The SGetTypeSRsrc function does not use the fNext flag (bit 2) because it always searches for the next sResource of the given type.

The SGetTypeSRsrc function returns values in the spSlot, spID, and spExtDev fields corresponding to the sResource that it found, and it returns 0 in the spParamData field if that sResource is enabled or 1 if it is disabled.

The SGetTypeSRsrc 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 SGetTypeSRsrc 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 SGetTypeSRsrc function are

Trap macro	Selector
_SlotManager	$000C

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	$000C

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 in the next section.