OpenUSB Developers Guide
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openusb_open_device,openusb_close_device

Name

openusb_open_device,openusb_close_device -- Open/Close a device

Synopsis

int32_t openusb_open_device(openusb_handle_t handle , openusb_devid_t devid , uint32_t flags , openusb_dev_handle_t *dev);

int32_t openusb_close_device(openusb_dev_handle_t dev);

Parameters

handle - Libusb handle.

devid - Device's devid.

flags - Initialization flag.

dev - Device handle

Description

openusb_open_device prepares a device and sets up internal data structures for use by openusb. openusb_close_device returns the opened device to its original state.

Application must call openusb_open_device() to open a device before it can do any USB transfers on that device. The open flags can be: 

    
           USB_INIT_DEFAULT		default behavior 
    
           USB_INIT_FAIL_FAST		fail if not immediately available 
    
           USB_INIT_REVERSIBLE	try platform dependent things that are
                                    guaranteed to be reversed on close 
    
           USB_INIT_NON_REVERSIBLE	try advanced platform dependent things that may
                                    not be guaranteed to be reversible on close

Upon successful open of a device, the device handle is returned in dev. All device associated operations will use this handle.

openusb_close_device() will destroy some internal data structures associated with the device handle dev.

Return Value

OPENUSB_SUCCESS - Success.

OPENUSB_NO_RESOURCES - Memory allocation failure.

OPENUSB_UNKNOWN_DEVICE - Can't find the device specified by devid.

OPENUSB_SYS_FUNC_FAILURE - System function fails.

OPENUSB_INVALID_HANDLE - Libusb handle is invalid.

OPENUSB_PLATFORM_FAILURE - Unspecified kernel/driver failure.

OPENUSB_IO_* - USB host controller errors

See Also

openusb_init, openusb_fini

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