#PHP Function that we know

echo("string"); // prints a string to the HTML file i.e. the web browser


# file operations

$fileptr = fopen("file.dat", "a"); // open file.dat for appending send 
//the current position in the file to $fileptr

fputs($fileptr, $phpvar."\t"); // put the contents of
// $phpvar appended with a tab into the "file.dat" at position $fileptr.

fputs($fileptr, $lastvar."\n"); // put the contents of 
// $lastvar appended with a return into the "file.dat" at position $fileptr.

fclose($fileptr); // closes the file referenced to by $fileptr.


# Sessioning
// sessioning allows you to save info between forms.  It handles many things
// like cookies and server data all behind the sceens so you dont have to


session_start(); // starts a session

session_register("HTMLvarname1"); // registers "HTMLvarname1" to the session
// note that we use the HTML variable name rather than the PHP names

session_register("var1","var2","var3"); //you can also do many at once

session_unregister("var1"); // takes var1 out of the session

session_destroy(); // delets all "cookies" and removes all parameters from
// a given session.  NOTE: you want to use this at the end of your form to 
// allow more than one user to submit the form from the same computer.


# Email
// example
mail("jonesn@union.edu", "My Subject", "Line 1\nLine 2\nLine 3");
mail($address,$subject,$body);