Give that you have a data structure (a collection of data of different types that are all about one thing) and that you have more than one of these data structures, pointers allow you to direct a subroutine to act on the data structure you desire without having to copy that structure into a temporary structure. For example, a linked list has a "node" datastructure for each entry in the list and a list traversal subroutine gets "pointed" to the current node and returns a pointer to the next node. PICs don't do linked lists very often, or any other even slightly complex structure, but when they do, its a good idea to use FSR as the parameter to routines that work on them. Does that help? James Newton, PICList Admin #3 mailto:jamesnewton@piclist.com 1-619-652-0593 phone http://www.piclist.com ----- Original Message ----- From: Lawrence Lile To: Sent: Friday, October 20, 2000 08:06 Subject: [PIC]: Pointers was Re: [PIC]: CCS - printing strings Some folks mentioned pointers in their responses to the earlier printing strings thread (which I still haven't got working, BTW) Pointers are always prefaced by "This is a really really important topic in C" which seems to make no sense to me. I've also written a lot of fine code without using them, so I become increasingly distressed that there is some basic concept I don't get! Now while I understand in a vague way what a pointer IS, I still have no understanding of why on earth someone would want to use it, ESPECIALLY in a tiny PIC. (not to mention I have had nothing but error messages when I try to use pointers, which is probably because I have no idea what they are for...) So the next topic is: Why does it make sense to use pointers in PIC code, in what situations? -- Lawrence -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! use mailto:listserv@mitvma.mit.edu?body=SET%20PICList%20DIGEST