Question

How to find string in binary file using only read(1) ?
For example I want to found position of string ‘abst’ in file ( without load to memory ) ?
It’s work but very primitive:

#!/usr/bin/python2
f = open("/tmp/rr", "rb")
f.seek(0)

cont = 1
while(cont):
    a1 = f.read(1)
    if a1 == 'a':
        a2 = f.read(1)
        if a2 == 'b':
            a3 = f.read(1)
            if a3 == 's':
                a4 = f.read(1)
                if a4 == 't':
                    found = True
                    cont = 0

Answer 1

You can find a substring by using the strings find-method.

content = file.read()
name = 'abst'
if name in content:
    slice = content.find(name)
    slice = slice, slice + len(name)

The read(1)-method is absolutely senseless. #see edit

Edit: more effiecient for the memory

def find(file, name):
    length = len(name)
    part = file.read(length)
    i = 0
    while True:
        if part == name:
            break
        char = file.read(1)
        if not char:
            return
        part = part[1:] + char
        i += 1
    return i, i + length, part

I see, using read(1) isn’t that senseless.