libusb_option enum

\ingroup libusb_lib Available option values for libusb_set_option() and libusb_init_context().

Inheritance

• Object
• Enum
• libusb_option

Available extensions

• EnumName

Values

LIBUSB_OPTION_LOG_LEVEL → const libusb_option

Set the log message verbosity.

This option must be provided an argument of type \ref libusb_log_level. The default level is LIBUSB_LOG_LEVEL_NONE, which means no messages are ever printed. If you choose to increase the message verbosity level, ensure that your application does not close the stderr file descriptor.

You are advised to use level LIBUSB_LOG_LEVEL_WARNING. libusb is conservative with its message logging and most of the time, will only log messages that explain error conditions and other oddities. This will help you debug your software.

If the LIBUSB_DEBUG environment variable was set when libusb was initialized, this option does nothing: the message verbosity is fixed to the value in the environment variable.

If libusb was compiled without any message logging, this option does nothing: you'll never get any messages.

If libusb was compiled with verbose debug message logging, this option does nothing: you'll always get messages from all levels.

const libusb_option(0)

LIBUSB_OPTION_USE_USBDK → const libusb_option

Use the UsbDk backend for a specific context, if available.

This option should be set at initialization with libusb_init_context() otherwise unspecified behavior may occur.

Only valid on Windows. Ignored on all other platforms.

const libusb_option(1)

LIBUSB_OPTION_NO_DEVICE_DISCOVERY → const libusb_option

Do not scan for devices

With this option set, libusb will skip scanning devices in libusb_init_context().

Hotplug functionality will also be deactivated.

The option is useful in combination with libusb_wrap_sys_device(), which can access a device directly without prior device scanning.

This is typically needed on Android, where access to USB devices is limited.

This option should only be used with libusb_init_context() otherwise unspecified behavior may occur.

Only valid on Linux. Ignored on all other platforms.

const libusb_option(2)

LIBUSB_OPTION_LOG_CB → const libusb_option

Set the context log callback function.

Set the log callback function either on a context or globally. This option must be provided an argument of type \ref libusb_log_cb. Using this option with a NULL context is equivalent to calling libusb_set_log_cb() with mode \ref LIBUSB_LOG_CB_GLOBAL. Using it with a non-NULL context is equivalent to calling libusb_set_log_cb() with mode \ref LIBUSB_LOG_CB_CONTEXT.

const libusb_option(3)

LIBUSB_OPTION_MAX → const libusb_option

const libusb_option(4)

Properties

hashCode → int

The hash code for this object.

no setter, inherited

index → int

A numeric identifier for the enumerated value.

no setter, inherited

name → String

Available on Enum, provided by the EnumName extension

The name of the enum value.

no setter

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

value → int

final

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

fromValue(int value) → libusb_option

Constants

values → const List<libusb_option>

A constant List of the values in this enum, in order of their declaration.