I was wondering how the “usb” utility gets information on the Product Name. I am fairly ignorant on how USB works.
Say, I execute the “usb -vv” command and part of its output is as follows:
…
Device Address : 2
Vendor : 0x04a9 (Canon)
Product : 0x1055 (BJC-85)
Device Release : r0.70
USB Spec Release : v1.10
Serial Number : 44OFBr
Class : 0x00 (Independent per interface)
Max PacketSize0 : 8
Languages : 0x0409 (English)
Configurations : 1
Configuration : 1
Attributes : 0x40 (Self-powered)
Max Power : 2 mA
Interfaces : 1
Interface : 0 / 0
Class : 0x07 (Printer)
Subclass : 0x01
Protocol : 0x02
Endpoints : 2 + Control
Endpoint : 0
Attributes : Control
Max Packet Size: 8
Endpoint : 1
Attributes : Bulk/OUT
Max Packet Size: 64
Endpoint : 2
Attributes : Bulk/IN
Max Packet Size: 64
…
So, in the line where it shows “Product : 0x1055 (BJC-85)”, I wish to know how this utility gets the string “BJC-85”. Does it get that string from a file or the device?
From what I understand from the enum-usb documentation, it supplies vendor id and device id along with other important USB descriptors, except the device name. Is my understanding correct?
Thanks in advance.