QUuid¶

PyQt5.QtCore.QUuid: Inherited by QBluetoothUuid.

Description¶

The QUuid class stores a Universally Unique Identifier (UUID).

Using Universally Unique IDentifiers (UUID) is a standard way to uniquely identify entities in a distributed computing environment. A UUID is a 16-byte (128-bit) number generated by some algorithm that is meant to guarantee that the UUID will be unique in the distributed computing environment where it is used. The acronym GUID is often used instead, Globally Unique IDentifiers, but it refers to the same thing.

Actually, the GUID is one variant of UUID. Multiple variants are in use. Each UUID contains a bit field that specifies which type (variant) of UUID it is. Call variant() to discover which type of UUID an instance of QUuid contains. It extracts the three most significant bits of byte 8 of the 16 bytes. In QUuid, byte 8 is QUuid::data4[0]. If you create instances of QUuid using the constructor that accepts all the numeric values as parameters, use the following table to set the three most significant bits of parameter b1, which becomes QUuid::data4[0] and contains the variant field in its three most significant bits. In the table, ‘x’ means don’t care.

msb0	msb1	msb2	Variant
0	x	x	NCS (Network Computing System)
1	0	x	DCE (Distributed Computing Environment)
1	1	0	Microsoft (GUID)
1	1	1	Reserved for future expansion

If variant() returns DCE, the UUID also contains a version field in the four most significant bits of QUuid::data3, and you can call version() to discover which version your QUuid contains. If you create instances of QUuid using the constructor that accepts all the numeric values as parameters, use the following table to set the four most significant bits of parameter w2, which becomes QUuid::data3 and contains the version field in its four most significant bits.

msb1	msb2	msb3	Version
0	0	1	Time
0	1	0	Embedded POSIX
0	1	1	Md5(Name)
1	0	0	Random
1	0	1	Sha1

The field layouts for the DCE versions listed in the table above are specified in the Network Working Group UUID Specification.

Most platforms provide a tool for generating new UUIDs, e.g. uuidgen and guidgen. You can also use createUuid(). UUIDs generated by createUuid() are of the random type. Their Version bits are set to Random, and their Variant bits are set to DCE. The rest of the UUID is composed of random numbers. Theoretically, this means there is a small chance that a UUID generated by createUuid() will not be unique. But it is a very small chance.

UUIDs can be constructed from numeric values or from strings, or using the static createUuid() function. They can be converted to a string with toString(). UUIDs have a variant() and a version(), and null UUIDs return true from isNull().

Enums¶

StringFormat

TODO

Member	Value	Description
Id128	TODO	TODO
WithBraces	TODO	TODO
WithoutBraces	TODO	TODO

Variant

This enum defines the values used in the variant field of the UUID. The value in the variant field determines the layout of the 128-bit value.

Member	Value	Description
DCE	2	Distributed Computing Environment, the scheme used by QUuid
Microsoft	6	Reserved for Microsoft backward compatibility (GUID)
NCS	0	Reserved for NCS (Network Computing System) backward compatibility
Reserved	7	Reserved for future definition
VarUnknown	-1	Variant is unknown

Version

This enum defines the values used in the version field of the UUID. The version field is meaningful only if the value in the variant field is DCE.

Member	Value	Description
EmbeddedPOSIX	2	DCE Security version, with embedded POSIX UUIDs
Md5	TODO	Alias for Name
Name	3	Name-based, by using values from a name for all sections
Random	4	Random-based, by using random numbers for all sections
Sha1	TODO	TODO
Time	1	Time-based, by using timestamp, clock sequence, and MAC network card address (if available) for the node sections
VerUnknown	-1	Version is unknown

Methods¶

__init__(): TODO

__init__(str): Creates a QUuid object from the string text, which must be formatted as five hex fields separated by ‘-‘, e.g., “{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}” where each ‘x’ is a hex digit. The curly braces shown here are optional, but it is normal to include them. If the conversion fails, a null UUID is created. See toString() for an explanation of how the five hex fields map to the public data members in QUuid.

See also

toString(), QUuid.

__init__(Union[QByteArray, bytes, bytearray]): TODO

__init__(QUuid): TODO

__init__(int, int, int, int, int, int, int, int, int, int, int): TODO

@staticmethod createUuid() → QUuid: TODO

@staticmethod createUuidV3(QUuid, Union[QByteArray, bytes, bytearray]) → QUuid: TODO

@staticmethod createUuidV3(QUuid, str) → QUuid: TODO

@staticmethod createUuidV5(QUuid, Union[QByteArray, bytes, bytearray]) → QUuid: TODO

@staticmethod createUuidV5(QUuid, str) → QUuid: TODO

__eq__(QUuid) → bool: TODO

@staticmethod fromRfc4122(Union[QByteArray, bytes, bytearray]) → QUuid: TODO

__ge__(QUuid) → bool: TODO

__gt__(QUuid) → bool: TODO

__hash__() → int: TODO

isNull() → bool: TODO

__le__(QUuid) → bool: TODO

__lt__(QUuid) → bool: TODO

__ne__(QUuid) → bool: TODO

__repr__() → str: TODO

toByteArray() → QByteArray: TODO

toByteArray(StringFormat) → QByteArray: TODO

toRfc4122() → QByteArray: TODO

toString() → str: TODO

toString(StringFormat) → str: TODO

variant() → Variant: TODO

version() → Version: TODO