Getting Started

Chapter 6: C Functions and Program Structures

int b = x + y + z – 12;

// do stuff

en a function calls itself. I’ve never called myself. I’m
en have to deal with the philosophical
s no problems with functions calling
themselves, other than the psychiatric problems it tends to cause programmers
when confronted with a recursive function and the task of figuring out what’s
going on. C Gurus love recursive functions.

unc(double data)

double ss;
e stuff
recursivefunc(mess);

very problematic in

limited in RAM memory. Each time you

stack using RAM that isn’t released until

ch function you call within a function puts more data on

more RAM. Recursive functions look like a good way

ably fill the stack leading to the often-fatal condition known

lly starts at the end of RAM and builds

start at the beginning of RAM and build

e stack may push it down far enough overwrite

mediately or only occasionally, like at the

ever written

or the same

int dosomething(int x, int y, int z)
{
int a = 0;

}

Recursion

Recursion happens wh
afraid that I might answer the phone and th
or psychiatric implications. However, C ha

void recursivef

{

me

// Do som

// Do more stuff
}

You’ll find recursion used quite appropriately in some standard library functions
and in many data sorting applications. But recursion can be
microcontrollers where we are usually
call a function some data is put on the
the function returns. Ea
the stack locking up
quickly and unpredict
as blowing your stack. Your stack usua
downward. Your variables usuall
on th

y
upward. So putting too much
variables. That may kill your code im
worse possible moment. Maybe I’m just not smart enough, but I’ve n
a recursive function for a microcontroller and I don’t plan on it. F
reason, I also try not to nest function calls too deep.