Tenho um diretório principalA com dois subdiretóriosB eC.

DirectoryB contém um arquivo de cabeçalhostructures.c:

#ifndef __STRUCTURES_H
#define __STRUCTURES_H
typedef struct __stud_ent__
{
    char name[20];
    int roll_num;
}stud;
#endif

DirectoryC contémmain.c code:

#include<stdio.h>
#include<stdlib.h>
#include <structures.h>
int main()
{
    stud *value;
    value = malloc(sizeof(stud));
    free (value);
    printf("working \n");
    return 0;
}

Mas eu recebo um erro:

main.c:3:24: error: structures.h: No such file or directory
main.c: In function ‘main’:
main.c:6: error: ‘stud’ undeclared (first use in this function)
main.c:6: error: (Each undeclared identifier is reported only once
main.c:6: error: for each function it appears in.)
main.c:6: error: ‘value’ undeclared (first use in this function)

Qual é a maneira correta de incluir ostructures.h arquivo emmain.c?