Binary File Parsing and Creation of new Files

[drd0s]

I have a file ( size : 20 mb | binary file ) that needs to be parsed every 820 bytes and that very content of 820 saved into a new file with the name of the file being the string(ASCII) between the 2byte and the 16byte mark.

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
^ THE FILENAME COMES FROM HERE ^

Ok now that the challenge is explained ( i hope ) what i do have for now is this :

#!/usr/bin/python
 
with open("file", "rb") as f:
    byte = f.read()
    if byte > 820:
        print "Reach the 1 record mark on the File you have defined "

Hmmm i don't know how to iterate every time i read the buffer and the f.read reaches 820 bytes and save it to a new file every 820bytes then the next 820bytes and continue to the end of the file .

[bvdet]

The io module is suitable for reading raw bytes. Read 840 bytes and save to an identifier. Write the 840 bytes out using a slice of the saved string (s[2:17] in your case) as the file name. Here's a simple example of using io.FileIO:

import io
f = io.FileIO(file_name)
while True:
    s = f.read(10)
    if not s:
        break
    print "******"
    print s
    print s[2:7]
    print "******"
f.close()

[drd0s]

nice i made after this my way that was like this :

n = 820
with open('/home/drdos/work/file.PDA', "rb") as f:
    while True:
        data = f.read(n)
        if not data:
            break
 
        filename = str(data[16:32])
 
        x = open(filename, 'wb').write(data)

[bvdet]

One thing you left off:

        x.close()

That ensures the data will be flushed to disk and you are not left with an open file.

Maybe you should use a try/except block in case filename has characters unsuitable for a file name.