pyall.py 文件源码

 复制代码def readFooter(numberOfBytes, fileptr):
        rec_fmt = '=BH'

        rec_len = struct.calcsize(rec_fmt)
        rec_unpack = struct.Struct(rec_fmt).unpack_from
        s = rec_unpack(fileptr.read(rec_len))
        ETX                = s[0]
        checksum           = s[1]
        # self.DatagramAsReceived = s[0].decode('utf-8').rstrip('\x00')
        # if numberOfBytes % 2 == 0:
        #     # skip the spare byte
        #     ETX                = s[2]
        #     checksum           = s[3]
        # else:        
        #     ETX                = s[1]
        #     checksum           = s[2]

        # #read any trailing bytes.  We have seen the need for this with some .all files.
        # if bytesRead < self.numberOfBytes:
        #     self.fileptr.read(int(self.numberOfBytes - bytesRead))

        return ETX, checksum

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