Belkin F8E211 Betriebsanweisung PDF herunterladen (Seite 96)

usbd

Get a string descriptor

Synopsis:

#include <sys/usbdi.h>

char *usbd_string( struct usbd_device *device,

_uint8 index,

int langid );

Arguments:

device An opaque handle used to identify the USB device.

index Index into the device’s (optional) string table.

langid Language ID. The usbd

languages

descriptor() function provides the

supported langids for the device. If you specify 0, the usbd

string()

function will select the ﬁrst/only supported language.

Library:

libusbdi

Description:

The usbd

string() function lets you obtain a string from the USB device’s table of

strings.

Typically, the string table may contain the names of the vendor, the product, etc. The

string table is optional.

Note that the strings are actually in Unicode/wide characters, so usb

string() also

conveniently converts them to UTF-8 (byte stream) for you.

Note that usbd

string() places the result string in a static buffer that’s reused every

time the function is called.

Returns:

A pointer to the string in an internal static buffer, or NULL on error.

Classiﬁcation:

QNX Neutrino, QNX 4

Safety

Cancellation point No

Interrupt handler No

continued. . .

82 Chapter 4 • USB Library Reference September 10, 2007

1 2 ... 91 92 93 94 95 96 97 98 99 100 101 ... 106 107

Keine Kommentare

Belkin F8E211 Betriebsanweisung Seite 96