NYCPHP Meetup

[Hans Zaunere]

--- Jim Musil <jim at nettmedia.com> wrote:
> On 1/29/03 4:22 PM, "Hans Zaunere" <hans at nyphp.org> wrote:
> 
> 
> > 
> > This is the right way; aside from using cURL :)  Or you could use real
> > sockets (as opposed to streams, of which fsockopen() is) if you have a
> lot of
> > time to kill.
> > 
> 
> 
> How exactly does PHP "open a socket"?

At the OS level, the same as anything else (ie telnet).

> Is it using something that is part of the PHP engine?

Partially; the nicety of being able to do fsockopen("udp://somewhere.com") or
fsockopen("tcp://somewhere.com") is a PHPism.  I think how PHP does this has
changed and/or improved to a certain extent recently, but I know little more
of the details.

http://www.php.net/manual/en/streams.php
http://www.php.net/manual/en/ref.stream.php

> or is it using some other system call?

Streams, whether stdio or PHP, all use the same system calls at one point;
they are just various wrappers.

> For instance, how close are the following operations?
> 
> 1.  Using fsockopen() to connect to port 80 on a remote server.
> 
> AND
> 
> 2.  Using the shell command telnet to connect to PORT 80 on a remote
> server.

As far as Linux, the OS, is concerned, identical.

> The reason I ask is both are moving very slowly on one of our Linux
> servers.
> I'm suspicious of xinetd because I had a previous problem with FTP'ing that
> was solved through xinetd's conf files.

I stay away from super-servers so maybe I've lost track of what it does, but
xinetd should only be involved with incoming connections (which, I suppose
*could* affect FTP).  But doing just a telnet should have no difference. 
Check DNS latency, network congestion, kernel/hardware errors, etc.


=====
Hans Zaunere
President, New York PHP
http://nyphp.org
hans at nyphp.org