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hwi_find_num_units()
Count the instances of a unit in the system page

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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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        Locate a specific instance of the named tag for a device
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hwi_find_num_units()

QNX SDP8.0C Library ReferenceAPIDeveloper

Count the instances of a unit in the system page

Synopsis:

#include <drvr/hwinfo.h>

int hwi_find_num_units( const char *name );

Arguments:

name: The name of the unit you want to count.

Library:

libdrvr

Use the -l drvr option to qcc to link against this library.

Description:

Multiple instances of a device or bus may exist in the hwinfo section of the system page. The hwi_find_num_units() function determines how instances of item name there are.

Returns:

The number of instances, or -1 if an error occurred.

Classification:

QNX OS


Safety:
Cancellation point	No
Signal handler	No
Thread	Yes

Page updated: December 04, 2024