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cpointersoperator-keywordnotation

What kind of operator is *(++ptr)?

I'm rather new to C and sometimes I come across strange notations, especially in relation with pointers.

A very short example:

....
real *ptr;
real delta_force;
for(i<particles;...)
{
  ...some calculations
  ptr=&FORCE(i,...);  //FORCE is a macro returning the current force on a particle
  *(++ptr) += delta_force;
  ...
 }
...

How can I interpret *(++ptr)?

Solution

  • First increment pointer and then add delta_force to the value pointed to by the pointer.

    *(++ptr) += delta_force;

    means same as

    ptr = ptr + 1;
*ptr = *ptr + delta_force;