How to read lines from a mmapped file?

Question

Is seems that the mmap interface only supports readline(). If I try to iterate over the object I get character instead of complete lines.

What would be the \"python

Answer 1

The following is reasonably concise:

with open(STAT_FILE, "r") as f:
    m = mmap.mmap(f.fileno(), 0, prot=mmap.PROT_READ)
    while True:
        line = m.readline()  
        if line == "": break
        print line
    m.close()

Note that line retains the newline, so you might like to remove it. It is also the reason why if line == "" does the right thing (an empty line is returned as "\n").

The reason the original iteration works the way it does is that mmap tries to look like both a file and a string. It looks like a string for the purposes of iteration.

I have no idea why it can't (or chooses not to) provide readlines()/xreadlines().