python vs. grep

[Ricardo Aráoz]

Ville Vainio wrote:
> On May 8, 8:11 pm, Ricardo Aráoz <ricar... at gmail.com> wrote:
> 
>> All these examples assume your regular expression will not span multiple
>> lines, but this can easily be the case. How would you process the file
>> with regular expressions that span multiple lines?
> 
> re.findall/ finditer, as I said earlier.
> 

Hi, sorry took so long to answer. Too much work.

findall/finditer do not address the issue, they merely find ALL the 
matches in a STRING. But if you keep reading the files a line at a time 
(as most examples given in this thread do) then you are STILL in trouble 
when a regular expression spans multiple lines.
The easy/simple (too easy/simple?) way I see out of it is to read THE 
WHOLE file into memory and don't worry. But what if the file is too 
heavy? So I was wondering if there is any other way out of it. Does grep 
read the whole file into memory? Does it ONLY process a line at a time?