Calling routines

[Anon]

I have just been told to use PHP instead of #Exec to call my routines. I have just studied the manual and I can't spot any way of calling a routine on my server. I don't really want to have more than about 3 lines of programming in any of my Web pages. I just want to call a routine to write some details to my log file.

Is there any instruction that will allow me to do this or do I always have to have heaps and heaps of code in all my web pages?

Sorry to ask something so elementary

[spacemax]

escapeshellcmd escape shell metacharacters
exec Execute an external program
system Execute an external program and display output
passthru Execute an external program and display raw output

[gregj]

require();