read and write binary data (newbie)

[Marcus Stojek]

Hi,

I am using Python quite a while for all kind of things. Now i have to
read a file (Windows) in binary format that contains strings (\0
terminated), int and floats (4 byte). and I am stunned because 
I don't know how to. 

to read strings I have written a function:
-----------------------------
def getstring(dat,maxlen=8):
    dummy=""
    spos=0
    while spos <= maxlen:
        c=dat.read(1)
        spos += 1
        if c!="\0" :
        	dummy += c
        else:
            return dummy
    return -1
----------------------------------

reading ints and floats is easy: 
x= dat.read(4)

but how can i convert x into a number?
and how can I write a float or int into
a binary file?

Could anybody please tell me where to look?

thanks
marcus