python从bin文件中逐字节读取时间太长

Question

i am trying to read the bytes from a bin file with the following code:

with open("filedata.bin","rb") as file:
   data = file.read()
   for byte in data:
         print byte

this works fine but the issue is that it takes too long (about 4 minutes). The goal is to read any byte of the bin file and send them over a serial interface.

My file is 101 kByte. Until now i didn't send any data over the serial interface. So this can not be the problem. I verify the rate over the python shell with the "print byte". It prints me the first byte to the last byte.

Does someone has an idea how i could read the bytes more quickly?

Answer 1

when using file.read() without any arguments, you read the entire file into memory at once. This is often slow.

To speed this up, you will want to read the file a few bytes at a time.

You can do this is by specifying how many bytes you want to read, for example:

with open("myfile", "rb") as f:
    byte = f.read(1)
    while byte:
        # do something with the byte
        byte = f.read(1)

A more advanced method to do this is to use the iter function:

for i in iter(lambda x: f.read(1), b""):
    # do something with the byte