python中二进制数据的CRC32，没有最后4个字节

Question

I am trying to get the CRC32 of some binary data, except for the last 4 bytes.

My code so far:

with open('filename.ext','rb') as f:
    fileContent = f.read()
    file_size, = struct.unpack("i",f.read(:4))
    print hex(file_size)

I know that the :4 is wrong and I am still looking for how not to read the last 4 bytes and then get the crc32 for the other data.

Answer 1

You can use indexing like this:

fileContent[:-4]

to skip the last 4 bytes.