diff --git a/src/templates_front/templator_front.org b/src/templates_front/templator_front.org
index 111184d..f1678b1 100644
--- a/src/templates_front/templator_front.org
+++ b/src/templates_front/templator_front.org
@@ -468,7 +468,7 @@ interface
    integer (c_int32_t) function trexio_read_$group_num$ (trex_file, num) bind(C)
      use, intrinsic :: iso_c_binding
      type (c_ptr), intent(in), value :: trex_file
-     integer (c_int64_t), value :: num
+     type (c_ptr), value :: num
    end function trexio_read_$group_num$
 end interface
 
diff --git a/src/test.f90 b/src/test.f90
index 00e410f..a95e6a1 100644
--- a/src/test.f90
+++ b/src/test.f90
@@ -7,18 +7,30 @@ program test_trexio
   type(c_ptr) :: file1
 
   integer :: rc 
-  integer (c_int64_t) :: num 
+  integer (c_int64_t) :: num
+
+  type(c_ptr) :: num_test 
+  integer, pointer :: num_read
+  integer, target :: num666
 
   rc = 0
   num = 10
 
+  num_test = c_loc(num666)
+
   file1 = trexio_open('trexio_test' // c_null_char, 'w', 1)
 !  file1 = trexio_open('test_fort.h5' // c_null_char, 'w', 0)
 
   rc = trexio_write_nucleus_num(file1, num)
-  if (rc == 0) write(*,*) 'SUCCESS 1'
+  if (rc == 0) write(*,*) 'SUCCESS WRITE'
+
+  rc = trexio_read_nucleus_num(file1, num_test)
+
+  call c_f_pointer(num_test, num_read)
+
+  if (rc == 0 .and. num_read == num) write(*,*) 'SUCCESS READ'
 
   rc = trexio_close(file1)
-  if (rc == 0) write(*,*) 'SUCCESS 2' 
+  if (rc == 0) write(*,*) 'SUCCESS CLOSE' 
 
 end program test_trexio