Module struct
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Module struct


Functions to convert between Python values and C structs.
Python strings are used to hold the data representing the C struct
and also as format strings to describe the layout of data in the C struct.

The optional first format char indicates byte order, size and alignment:
 @: native order, size & alignment (default)
 =: native order, std. size & alignment
 <: little-endian, std. size & alignment
 >: big-endian, std. size & alignment
 !: same as >

The remaining chars indicate types of args and must match exactly;
these can be preceded by a decimal repeat count:
 x: pad byte (no data); c:char; b:signed byte; B:unsigned byte;
 h:short; H:unsigned short; i:int; I:unsigned int;
 l:long; L:unsigned long; f:float; d:double.
Special cases (preceding decimal count indicates length):
 s:string (array of char); p: pascal string (with count byte).
Special case (only available in native format):
 P:an integer type that is wide enough to hold a pointer.
Special case (not in native mode unless 'long long' in platform C):
 q:long long; Q:unsigned long long
Whitespace between formats is ignored.

The variable struct.error is an exception raised on errors.


Version: 0.1

Classes [hide private]
error
Functions [hide private]
 
_compile(fmt)
 
calcsize(fmt)
Return size of C struct described by format string fmt.
 
pack(fmt, *args)
Return string containing values v1, v2, ...
 
pack_into(fmt, buf, offset, *args)
Pack the values v1, v2, ...
 
unpack(fmt, s)
Unpack the string, containing packed C structure data, according to fmt.
 
unpack_from(fmt, buf, offset=0)
Unpack the buffer, containing packed C structure data, according to fmt starting at offset.
Variables [hide private]
  _MAXCACHE = 100
  _cache = {}

Imports: Struct


Function Details [hide private]

calcsize(fmt)

 

Return size of C struct described by format string fmt. See struct.__doc__ for more on format strings.

pack(fmt, *args)

 

Return string containing values v1, v2, ... packed according to fmt. See struct.__doc__ for more on format strings.

pack_into(fmt, buf, offset, *args)

 

Pack the values v1, v2, ... according to fmt, write the packed bytes into the writable buffer buf starting at offset. See struct.__doc__ for more on format strings.

unpack(fmt, s)

 

Unpack the string, containing packed C structure data, according to fmt. Requires len(string)==calcsize(fmt). See struct.__doc__ for more on format strings.

unpack_from(fmt, buf, offset=0)

 

Unpack the buffer, containing packed C structure data, according to fmt starting at offset. Requires len(buffer[offset:]) >= calcsize(fmt). See struct.__doc__ for more on format strings.