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C Library Reference
H
hwi_tag2off()
Return the offset from the start of the hwinfo area of the system page

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        Find a specific item instance owned by a specific parent, resolving all synonym names
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        Find the offset of the section in the system page for a bus
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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
      - hwi_next_tag()
        Find the next tag in the hwinfo structure
      - hwi_off2tag()
        Return a pointer to the start of a tag in the hwinfo area of the system page
      - hwi_tag2off()
        Return the offset from the start of the hwinfo area of the system page
      - hwi_tag_find()
        Locate a specific instance of the named tag for a device
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        Get attributes of a bus or device
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        Find a bus attribute tag associated with a bus
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        Find the clock source for a device
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        Find an erratum for a device
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        Find the interrupt vector associated with a device
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        Get the NIC address of 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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This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

hwi_tag2off()

QNX SDP8.0C Library ReferenceAPIDeveloper

Return the offset from the start of the hwinfo area of the system page

Synopsis:

#include <hw/sysinfo.h>

unsigned hwi_tag2off( void *tag );

Arguments:

tag: A pointer to a tag in the hwinfo area of the system page.

Library:

libc

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

Description:

Given a pointer to the start of a tag, the hwi_tag2off() function returns the offset, in bytes, from the beginning of the start of the hwinfo section.

Returns:

The offset of the tag, in bytes.

Classification:

QNX OS


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: December 04, 2024