How to get hex string from signed integer

Question

Say I have the classic 4-byte signed integer, and I want something like

print hex(-1)

to give me something like

0xffffffff

In reality, the above gives me -0x1. I'm dawdling about in some lower level language, and python commandline is quick n easy.

So.. is there a way to do it?

Answer 1

This will do the trick:

>>> print(hex (-1 & 0xffffffff))
0xffffffff

or, a variant that always returns fixed size (there may well be a better way to do this):

>>> def hex3(n):
...     return "0x%s"%("00000000%s"%(hex(n&0xffffffff)[2:-1]))[-8:]
...
>>> print hex3(-1)
0xffffffff
>>> print hex3(17)
0x00000011

Or, avoiding the hex() altogether, thanks to Ignacio and bobince:

def hex2(n):
    return "0x%x"%(n&0xffffffff)

def hex3(n):
    return "0x%s"%("00000000%x"%(n&0xffffffff))[-8:]

Answer 2

Try this function:

'%#4x' % (-1 & 0xffffffff)