1USB_IFNUM_TO_IF(9)               USB Core APIs              USB_IFNUM_TO_IF(9)
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NAME

6       usb_ifnum_to_if - get the interface object with a given interface
7       number
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SYNOPSIS

10       struct usb_interface * usb_ifnum_to_if(const struct usb_device * dev,
11                                              unsigned ifnum);
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ARGUMENTS

14       dev
15           the device whose current configuration is considered
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17       ifnum
18           the desired interface
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DESCRIPTION

21       This walks the device descriptor for the currently active configuration
22       and returns a pointer to the interface with that particular interface
23       number, or null.
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25       Note that configuration descriptors are not required to assign
26       interface numbers sequentially, so that it would be incorrect to assume
27       that the first interface in that descriptor corresponds to interface
28       zero. This routine helps device drivers avoid such mistakes. However,
29       you should make sure that you do the right thing with any alternate
30       settings available for this interfaces.
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32       Don´t call this function unless you are bound to one of the interfaces
33       on this device or you have locked the device!
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36Kernel Hackers Manual 2.6.         June 2019                USB_IFNUM_TO_IF(9)
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