hwitag_find_busattr()

Arguments:

hwi_off

The offset into the hwinfo section of the system page for the device, which you can get by calling hwi_find_device().

busattr_idx

The index of the bus attribute; see below.

busattr

A pointer to a struct hwi_busattr where the function can store the attribute.

Library:

libdrvr

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

Description:

You can use hwitag_find_busattr() to find one or more bus attribute tags associated with the bus at hwi_off in the hwinfo section of the system page.

If the specified bus attribute tag exists and busattr isn't NULL, the retrieved bus attributes are placed in *busattr.

Some buses contain multiple sets of attributes. You can retrieve all of them by using the busattr_idx parameter as follows:

• On the first call, set *busattr_idx to 0. The first bus attribute (if one exists) is returned in *busattr.
• You can then continue to call hwitag_find_busattr() with the same arguments until NULL is returned.
• If you know that there's more than one set of bus attributes for the specified bus, you can set *busattr_idx to the entry number of the desired attribute tag. If that entry exists, it's returned. For example, to obtain the third bus attribute for hwi_off, set *busattr_idx to 2 (base-0 indexing applies).
• If you're interested only in the first attribute, you can pass NULL for busattr_idx (which is the same as setting *busattr_idx to 0).

Returns:

0 on success (independent of whether busattr is NULL), or -1 on error.

Classification:

QNX OS