Introduction

     Despite the many capabilities of CA-Clipper Tools, there are times when
     direct port or memory access is needed.  The functions in this chapter
     serve this purpose.  For example, you can read memory regions by byte,
     word, or as a string through the PEEK function.  POKE functions enable
     you to write a byte or word to working memory, but not a string.

     Warning!  POKE functions can be very dangerous.  If you write to the
     wrong area in memory it can cause a lot of problems you may not foresee.
     Use POKE functions ONLY if you have extensive system knowledge.

     This also applies to all the IN/OUT functions in this chapter, which
     allow you to directly manipulate a port.  For example, if you address a
     disk controller improperly, the result may lead to data loss.