views:

83

answers:

3

I need to create a Python string consisting of non-ascii bytes to be used as a command buffer in a C module. I can do that if I write the string by hand:

mybuffer = "\x00\x00\x10"

But I cannot figure out how to create the string on the fly if I have a set of integers which will become the bytes in the string. Concatenating an integer with a string is a TypeError.

So if I have a list of integers lets say:

myintegers = [1, 2, 3, 10]

How can I convert that into a string "\x01\x02\x03\x0A"

I am using Python 2.6.

+2  A: 

u''.join(map(unichr, myintegers)) will do what you want nicely.

JasonFruit
Leave off the leading `u` and use `chr` instead of `unichr` if you won't go above 256.
JasonFruit
Better yet, use `b''` so that 2to3 will recognize it as `bytes` instead of `str`.
dan04
A: 
In [28]: import struct

In [29]: struct.pack('{0}B'.format(len(myintegers)),*myintegers)
Out[29]: '\x01\x02\x03\n'

Note that

In [47]: '\x01\x02\x03\n'=="\x01\x02\x03\x0A"
Out[47]: True
unutbu
+1  A: 

Python 2.X

''.join(chr(i) for i in myintegers)

Python 3.X

bytes(myintegers)
Mark Tolonen