Novice question.

[John Gordon]

jmwojtal at vela.acs.oakland.edu (Wojo) writes:

>What exactly are the reasons "register" and "extrn" are used to declare
>values.  I see register alot in some of the programs and I don't know why
>they do it.  Is it just good practice or what.

	"register" means that the variable will be stored in a portion of
memory that can be accessed significantly faster than normal.  Useful for 
loop counters, among other things.  There are a limited number of registers
available.  MS-DOS machines, for example, have around 16 (I think).

	"extern" means that the variable is global, and was declared in a
separate .c file.  If your program occupies only 1 file, you will never
use this.


---
John Gordon
Internet: gordon at osiris.cso.uiuc.edu        #include <disclaimer.h>
          gordon at cerl.cecer.army.mil       #include <clever_saying.h>
GEnie:    j.gordon14