/* This program shows a calluser program using  */
/* TPU$EXECUTE_COMMAND to provide information   */
/* to VAXTPU                                    */

#include descrip
#include math
#include ssdef

int tpu$handler ();

tpu$calluser (code, instring, outstring)
int *code;
struct dsc$descriptor *instring, *outstring;
{
    int status;
    struct dsc$descriptor_d execute_desc;
    char execute_string [128];
    int len;

    if (*code != 0) srand (*code);
    sprintf (execute_string,
             "random_int := %d;",
             rand ());
             
    execute_desc.dsc$w_length = 0;
    execute_desc.dsc$b_dtype = DSC$K_DTYPE_T;
    execute_desc.dsc$b_class = DSC$K_CLASS_D;
    execute_desc.dsc$a_pointer = 0;
    len = strlen (execute_string);
    status = lib$scopy_r_dx (&len, 
                             execute_string,
                             &execute_desc);
    if (status != SS$_NORMAL) return status;

    lib$establish (tpu$handler);
    return tpu$execute_command (&execute_desc);
}
<endcode_example>


!
! A VAXTPU command file showing that a
! calluser program can modify VAXTPU 
! variables using TPU$EXECUTE_COMMAND
!
random_int := 0;
ignore := call_user (1, "");
message (str(random_int));
ignore := call_user (0, "");
message (str(random_int));
ignore := call_user (0, "");
message (str(random_int));
ignore := call_user (0, "");
message (str(random_int));
ignore := call_user (0, "");
message (str(random_int));
message ("");
ignore := call_user (1, "");
message (str(random_int));