Node:Another variable parameter example, Previous:Passing pointers correctly, Up:Variable parameters
Another variable parameter example
There is nothing mysterious about pointers, but they can be tricky. Here is another example.
Notice that the pointers in both this example and the example above are
dereferenced with asterisks before they are used (for instance, when the
contents of the location pointed to by height_ptr
are multiplied
by the integer hscale
with the line *height_ptr =
*height_ptr * hscale;
in the function scale_dimensions
below).
#include <stdio.h> int main(); void scale_dimensions (int *, int *); /* Scale some measurements */ int main() { int height,width; height = 4; width = 5; scale_dimensions (&height, &width); printf ("Scaled height = %d\n", height); printf ("Scaled width = %d\n", width); return 0; } void scale_dimensions (int *height_ptr, int *width_ptr) { int hscale = 3; /* scale factors */ int wscale = 5; *height_ptr = *height_ptr * hscale; *width_ptr = *width_ptr * wscale; }