passing arguments to _beginthread() -- whats wrong?
10,056
arg
is a local variable defined in foo
- it would be destroyed as soon as that function ends, but myFunc
which is running in another thread would still be trying to access it. You should allocate arg
on the heap and destroy it in the thread after you are done.
void foo(int a, int b) {
HANDLE handle;
t *arg;
arg = (t *)malloc(sizeof(t));
arg->data1 = a;
arg->data2 = b;
handle = (HANDLE) _beginthread( myFunc, 0, (void*) arg);
}
void myFunc(void *param) {
t *args = (t*) param;
int x = args->data1;
int y = args->data2;
printf("x=%d, y=%d\n", x, y);
free(args);
}
Also note that HANDLE
should be all caps.
Author by
emge
Updated on June 04, 2022Comments
-
emge about 2 years
I have this code and I am not getting the expected results... whats wrong?
typedef struct { int data1; int data2; }t; void foo(int a, int b) { Handle handle; t arg; arg.data1 = a; arg.data2 = b; handle = (HANDLE) _beginthread( myFunc, 0, (void*) &arg); } void myFunc(void *param) { t *args = (t*) param; int x = args->data1; int y = args->data2; printf("x=%d, y=%d\n", x, y); }