How to pop the stack and keep track of charFlag, in C?

Question

/* Below is am popping the stack, which works, but it does not keep track of the charFlag variable that is pushed onto the stack. Can you help me with modifying this *char pop (stackNodePtr ptr) so when it pops the value from the stack, and keeps track of the charFlag?
Thank you very much in advance for your assistance!!!
Note: This posts is an offspring of my previous question: _"Why is the stack, written in C, converting + to ascii 42 ?"_. I want to thank Xnav for the excellent suggestion of including a character flag to keep track of the datatype being pushed onto the stack. Thank you etresoft for variable renaming comment.
typedef struct stackNode {
int value;
int charFlag;
struct stackNode *next;
}stackNode;
typedef stackNode * StackNodePtr;
char pop( StackNodePtr *ptr )
if( StackIsEmpty(*ptr))
printf("
Pop attempted, but the Stack is empty, or underflow");
exit(2);//needed stdlib.h to work
else
char sTop;
StackNodePtr old;
if( (old = (StackNodePtr ) malloc( sizeof (StackNodePtr) )) == NULL )
printf("
No memory left for pop operation");
sTop = (*ptr)->value;
old = *ptr;
*ptr = (*ptr)->next;
free(old);
return (sTop);

Answer 1

//I added a global variable int gCharFlag to keep track of the popped charFlag. Will the code below work, or should I just return (*ptr)? Thank you once again!
//struct, typedef and gCharFlag are stored inside of a .h file
typedef struct stackNode {
int value;
int charFlag;
struct stackNode *next;
}stackNode;
typedef stackNode * StackNodePtr;
int gCharFlag;//global variable, which is stored inside of a .h file
//below method is stored inside of a .c file
char pop( StackNodePtr *ptr )
if( StackIsEmpty(*ptr))
printf("
Pop attempted, but the Stack is empty, or underflow");
exit(2);//needed stdlib.h to work
else
char sTop;
StackNodePtr old;
if( (old = (StackNodePtr ) malloc( sizeof (StackNodePtr) )) == NULL )
printf("
No memory left for pop operation");
sTop = (*ptr)->value;
gCharFlag = (*ptr)->charFlag;
old = *ptr;
*ptr = (*ptr)->next;
free(old);
return (sTop);//to return the struct node, then it would be return (*ptr), correct?