Speed problems with Python vs. Perl

[Carlos Alberto Reis Ribeiro]

At 15:37 28/03/01 +0000, Fredrik Lundh wrote:
>for a backwards-compatible version of xreadlines, use
>the double-loop pattern from:
>
>http://effbot.org/guides/readline-performance.htm

Looking at your code there, a saw readline-example-3.py:

# readline-example-3.py
file = open("sample.txt")
while 1:
   lines = file.readlines(100000)
     if not lines:
       break
     for line in lines:
       pass # do something

Then I got to the library reference manual:

readlines ([sizehint])
   Read until EOF using readline() and return a list containing the
   lines thus read. If the optional sizehint argument is present,
   instead of reading up to EOF, whole lines totalling approximately
   sizehint bytes (possibly after rounding up to an internal buffer
   size) are read. Objects implementing a file-like interface may choose
   to ignore sizehint if it cannot be implemented, or cannot be
   implemented efficiently.


I think that this must be new on Python 2.0; I really dont remember it from 
my 1.5.2 days (maybe I overlooked it). So I have two questions:

1) What platforms do implement this? DO I need to check the code to have 
this information?
2) There is any documentation about buffer sizes for different platforms?


Carlos Ribeiro