[Tutor] Re: Reading text lines from a socket

[Bob Ippolito]

The real solution is just to use a layer of abstraction, like 
asyncore/medusa, Twisted, etc.  Relying on the fact that your operating 
system may or may not allow a socket to act sort of like a file is 
really not something you should do, from Python or otherwise.

socket.makefile is platform specific, at best.

On 2004-02-28 20:28:59 -0500, Lloyd Kvam <pythontutor at venix.com> said:

> Well, I've never used it, but sockets do have the makefile method.  That
> would seem to fit what you're trying to do.
> 
> Sandip Bhattacharya wrote:
> 
>> [Reposting to the general list too]
>> 
>> Lloyd Kvam wrote:
>> 
>>> Sockets deal with packetized data.  The network protocols do not guarantee
>>> keeping the data in line oriented chunks - even if the data starts out 
>>> that way.
>>> 
>>> You need to deal with extracting lines from chunks.  So long as the 
>>> connection is
>>> working properly, this is easy.  The challenge occurs when the 
>>> remainder of a line
>>> never gets delivered.  The best strategy depends upon the details of 
>>> what you are
>>> doing.
>> 
>> 
>> I understand that. In Python using sockets is like using sockets in C.
>> 
>> However, I was looking for a python equivalent of the perl idiom of 
>> opening a socket and getting a file handle ... and then reading this 
>> file handle as any other line oriented file using $socket->readline
>> 
>> I am trying to write a simple Netcraft style script which tries the 
>> HEAD method on a webserver and reads the Server: header from the 
>> response. I would not like to use urllib, because even a call to 
>> something like urllib.info() reads in the complete webpage on an open().
>> 
>> Even if this particular problem could be done elegantly, I would be 
>> interested to know the answer to my original question because the 
>> feature of reading a line at a time from a socket will help me in a lot 
>> of other places in the future.
>> 
>> - Sandip