The struct Module
The struct module shown in Example 4-6 contains functions to convert between binary strings and Python tuples. The pack function takes a format string and one or more arguments, and returns a binary string. The unpack function takes a string and returns a tuple.
Example 4-6. Using the struct Module
File: struct-example-1.py
import struct
# native byteorder
buffer = struct.pack("ihb", 1, 2, 3)
print repr(buffer)
print struct.unpack("ihb", buffer)
# data from a sequence, network byteorder
data = [1, 2, 3]
buffer = apply(struct.pack, ("!ihb",) + tuple(data))
print repr(buffer)
print struct.unpack("!ihb", buffer)
# in 2.0, the apply statement can also be written as:
# buffer = struct.pack("!ihb", *data)
' 01 00 00 00 02 00 03'
(1, 2, 3)
' 00 00 00 01 00 02 03'
(1, 2, 3)
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