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hwi_off2tag()
Return a pointer to the start of a tag in the hwinfo area of the system page

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        Find a specific instance of an device by its compatible string
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        Find the offset in the system page of a device
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        Find the bus that a device belongs to
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        Find an item in the hwinfo structure
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        Count the instances of a unit in the system page
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        Find a tag in the hwinfo structure
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        Determine which instance of a device an offset corresponds to
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        Find the next item in the hwinfo structure
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        Find the next tag in the hwinfo structure
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        Return a pointer to the start of a tag in the hwinfo area of the system page
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        Return the offset from the start of the hwinfo area of the system page
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        Locate a specific instance of the named tag for a device
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        Find a bus attribute tag associated with a bus
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        Find the interrupt vector associated with a device
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        Find the PHY address associated with a device
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        Calculate the length of the hypotenuse for a right-angled triangle
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hwi_off2tag()

QNX SDP8.0C Library ReferenceAPIDeveloper

Return a pointer to the start of a tag in the hwinfo area of the system page

Synopsis:

#include <hw/sysinfo.h>

void * hwi_off2tag( unsigned offsect );

Arguments:

offsect: The offset, in bytes from the start of the hwinfo section, of a tag.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The hwi_off2tag() function returns a pointer to the start of the tag, given an offset.

Returns:

A pointer to the start of the tag.

Examples:

See hwi_next_item().

Classification:

QNX OS


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: December 04, 2024