[Function]
void *SMTA_MakeAction(void *execadd)

Search for an unused action (id = 0), register the action execution address in pcbuff, and activate the action (id = 1).
∙ In this function, it is undefined which number of actions is registered in the array. This may cause inconveniences when comparing action information. For example, when taking a collision between a shot and a player.
If you need to manage by yourself what number is registered in the array, use the following function.