Just send the appropriate escape sequence, afaik this should work:

echo chr(27), "[2H";

almost ;-)

<?php
echo chr(27), "[H", chr(27), "[2J";
?>

Thanks Derick, this is exactly the kind of thing that I was looking for.  Unfortunately, as I make it out, there is a problem (and I here document the steps):

For this to work ANSI.sys must be a driver for the command prompt, but this will only work under COMMAND.COM.  To do this, as described at
http://www.evergreen.edu/biophysics/technotes/program/ansi_esc.htm
and http://support.microsoft.com/default.aspx?scid=kb;en-us;Q101875
I first edit my \windows\system32\CONFIG.NT file by adding to the three existing lines:
dos=high, umb
device=%SystemRoot%\system32\himem.sys
files=4

the following two lines:
DEVICEhigh=%systemroot%\system32\ANSI.SYS
dosonly

and save it as CONFIGDS.NT

Now I create a new shortcut in windows and point it to \windows\system32\COMMAND.COM  In the advanced section under the Program tab, for Config filename I put:
%SystemRoot%\SYSTEM32\CONFIGDS.NT

For testing, I make a batch file with a one line entry:
echo {ESC}[2J
where that {ESC} is the escape character (hex 1B)
If I run the batch file, the screen is reset to my expectations.

UNFORTUNATELY, when I try to run PHP, I get the following message:
This program cannot be run in DOS mode.

Unless I've missed something in seems like PHP and the ANSI control codes are mutually exclusive on Win XP and Win 2K.

Csaba

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