2013/5/29 Hans de Goede <hdego...@redhat.com>: > Hi, > > On 05/29/2013 12:08 AM, Tim Roberts wrote: >> Hans de Goede wrote: >>> I would like to give libusb using applications to os cached string >>> descriptors, so that those can be accessed without the need to open a >>> device and do io on it. >> >> The device is already open, because your API requires a libusb_device, >> right? > > Nope, a libusb_device is just a software struct representing the info > we could get from the OS about the device without actually opening > it, or talking to the device. An opened device is represented by > a libusb_handle. > >> So, you're saving the cost of one device descriptor read, and >> two string descriptor reads. > > What I'm saving is opening the device (which under Linux requires rights > the app often won't have), and slow and expensive io to the device, which > includes waking it up from sleep, thus burning battery on portable devices.
OK. I understand now. I agree with the new calls libusb_get_vendor_string/libusb_get_product_string. I am not a strong supporter of the use of usbids but why not. Bye -- Dr. Ludovic Rousseau ------------------------------------------------------------------------------ Introducing AppDynamics Lite, a free troubleshooting tool for Java/.NET Get 100% visibility into your production application - at no cost. Code-level diagnostics for performance bottlenecks with <2% overhead Download for free and get started troubleshooting in minutes. http://p.sf.net/sfu/appdyn_d2d_ap1 _______________________________________________ libusbx-devel mailing list libusbx-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libusbx-devel
