Python: how to get part of file by size

Question

I would like to read just one part (not chunks) from a txt-file (10GB) with lines and write them into another file. The size of the part should be exactly 25MB.

I have tried with linecache.getlines, but it was not very exactly. Thanks.

Answer 1

A simple way to perform the split is to use read(), assuming each character is a byte.

for nameadd in range(10*1024/25):
    f = open('fname.txt')
    saveTxt = f.read(25*(1024**2))
    fSave = open(str(nameadd)+'fname.txt','w')
    fSave.write('%s',saveTxt)