How to read complete file with bitstring

Question

I want to read as many 24 bit chunks as possible from a file. How can I do this using bitstrings' ConstBitStream when I don't now how many chunks there are?

Currently I do this:

eventList = ConstBitStream(filename = 'events.dat')
for i in range(1000) :
    packet = eventList.read(24)

(here I have to calculate the number of events beforehand)

score 5 · Accepted Answer · answered Jun 05 '12 at 08:50

5

You could read until an ReadError exeption is generated

try:
    while True:
        packet = eventList.read(24)
except ReadError:
    pass

answered Jun 05 '12 at 08:50

waynix

501
3
13

1

`ReadError` is a `bitstring` exception. It has to be either imported from `bitstring` or used as `bitstring.ReadError`. – TheMeaningfulEngineer Jun 03 '13 at 14:58

score 3 · Answer 2 · answered Jun 05 '12 at 09:40

3

Catching the ReadError is a perfectly good answer, but another way is to instead use the cut method, which returns a generator for bitstrings of a given length, so just

for packet in eventList.cut(24):

should work.

answered Jun 05 '12 at 09:40

Scott Griffiths

21,438
8
55
85

How to read complete file with bitstring

2 Answers2