Using a function pointer [closed] - c

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I have a function in C that is crashing my code and I'm having a hard time figuring out what is going on. I have a function that looks like this:
#define cond int
void Enqueue(cond (*cond_func)());
cond read() {
return IsEmpty(some_global); // Returns a 1 or a 0 as an int
}
Enqueue(&read);
However, when running the above, it segfaults as soon as Enqueue is called. It doesn't even execute anything inside the function. I ran gdb and it just shows it dying as soon as Enqueue is called- no statements are processed within it. Any idea what is going on? Any help would be appreciated.

Answer 1

Can you give more information about the code because according to my interpretation the code is working fine.I have tried this-
#define cond int
void Enqueue(cond (*cond_func)());
cond read()
{
int some_global=1;
return IsEmpty(some_global); // Returns a 1 or a 0 as an int
}
int IsEmpty()
{
return 1;
}
void Enqueue(cond (*cond_func)())
{
printf("Perfect");
return 0;
}
int main()
{
Enqueue(&read);
return 0;
}
And it is working fine.

Answer 2

#define cond int
was meant to be:
typedef int cond;
Although defining an alias for your function pointer might be much more reasonable here, for example:
typedef int (*FncPtr)(void);
int read() {
printf("reading...");
}
void foo(FncPtr f) {
(*f)();
}
int main() {
foo(read);
return 0;
}

Answer 3

This works fine:
#include <stdio.h>
#include <stdbool.h>
typedef bool cond;
void Enqueue(cond (*cond_func)(void)) {
printf("In Enqueue()...\n");
cond status = cond_func();
printf("In Enqueue, 'status' is %s\n", status ? "true" : "false");
}
bool IsEmpty(const int n) {
return true;
}
cond my_cond_func(void) {
printf("In my_cond_func()...\n");
return IsEmpty(1);
}
int main(void) {
Enqueue(my_cond_func);
return 0;
}
Your problem is likely coming from somewhere else, such as your definition of Enqueue() which you don't provide, or the fact your function is called read() and is conflicting with the more common function of that name.