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struct – Pack and unpack primitive data types.

Pack and unpack primitive data types.

This module implements a subset of the corresponding CPython module, as described below. For more information, refer to the original CPython documentation: struct.

The following byte orders are supported:

Character	Byte order	Size	Alignment
@	native	native	native
<	little-endian	standard	none
>	big-endian	standard	none
!	network (= big-endian)	standard	none

The following data types are supported:

Format	C Type	Python type	Standard size
b	signed char	integer	1
B	unsigned char	integer	1
h	short	integer	2
H	unsigned short	integer	2
i	int	integer (1)	4
I	unsigned int	integer (1)	4
l	long	integer (1)	4
L	unsigned long	integer (1)	4
q	long long	integer (1)	8
Q	unsigned long long	integer (1)	8
e	n/a (half-float)	float (2)	2
f	float	float (2)	4
d	double	float (2)	8
s	char[]	bytes
P	void *	integer

Functions

calcsize(→ int)	Return the number of bytes needed to store the given fmt.
pack(→ bytes)	Pack the values v1, v2, ... according to the format string fmt.
pack_into(→ _typeshed.Incomplete)	Pack the values v1, v2, ... according to the format string fmt
unpack(→ Tuple)	Unpack from the data according to the format string fmt.
unpack_from(→ Tuple)	Unpack from the data starting at offset according to the format string

Module Contents

struct.calcsize(fmt) → int

Return the number of bytes needed to store the given fmt.

struct.pack(fmt, v1, *args, **kwargs) → bytes

Pack the values v1, v2, … according to the format string fmt. The return value is a bytes object encoding the values.

struct.pack_into(fmt, buffer, offset, v1, *args, **kwargs) → Incomplete

Pack the values v1, v2, … according to the format string fmt into a buffer starting at offset. offset may be negative to count from the end of buffer.

struct.unpack(fmt, data) → Tuple

Unpack from the data according to the format string fmt. The return value is a tuple of the unpacked values.

struct.unpack_from(fmt, data, offset=0) → Tuple

Unpack from the data starting at offset according to the format string fmt. offset may be negative to count from the end of data. The return value is a tuple of the unpacked values.