#include <stdio.h>
#include <stdlib.h>

typedef struct externalStruct{
    int  msgID;
    struct internalStruct {     
        long someValue;
    } *internalStruct ;
} externalStruct_t;

int main(void) {
    externalStruct_t* newExternalStruct = malloc(sizeof(externalStruct_t));
    newExternalStruct->internalStruct = malloc(sizeof(*newExternalStruct->internalStruct));
    return 0;
}