# NAG Library Routine Document

## 1Purpose

x10bb_a1w_f inserts the locations of cb_handle and of companion AD callback into the internal data structure used by the NAG AD Library.

## 2Specification

Fortran Interface
 Subroutine x10bb_a1w_f (
 Integer, Intent (Inout) :: ifail Type (c_ptr), Intent (In) :: cb_handle Type (c_funptr), Intent (In) :: cb_loc
extern "C" {
 void x10bb_a1w_f_ (void *&cb_handle, void *&cb_loc, Integer &ifail)
}
 Declare PtrSafe Sub X10BBF Lib "libname" ( _ cb_handle As LongPtr, cb_loc As LongPtr, ifail As Long)

## 3Description

x10bb_a1w_f inserts the locations of cb_handle and of companion AD callback into the internal data structure used by the NAG AD Library.

None.

## 5Arguments

1:     $\mathbf{cb_handle}$ – Type (c_ptr)Input
On entry: a handle to the callback data object as created by a prior call to x10ba_a1w_f.
2:     $\mathbf{cb_loc}$ – Type (c_funptr)Input
On entry: the location of the user-supplied AD symbolic callback as returned by the intrinsic c_funloc with the callback name the same as the argument.
3:     $\mathbf{ifail}$ – IntegerInput/Output
On entry: ifail must be set to $0$, . If you are unfamiliar with this argument you should refer to Section 3.4 in How to Use the NAG Library and its Documentation for details.
For environments where it might be inappropriate to halt program execution when an error is detected, the value  is recommended. If the output of error messages is undesirable, then the value $1$ is recommended. Otherwise, if you are not familiar with this argument, the recommended value is $0$. When the value  is used it is essential to test the value of ifail on exit.
On exit: ${\mathbf{ifail}}={\mathbf{0}}$ unless the routine detects an error or a warning has been flagged (see Section 6).

## 6Error Indicators and Warnings

If on entry ${\mathbf{ifail}}=0$ or $-1$, explanatory error messages are output on the current error message unit (as defined by x04aaf).
Errors or warnings detected by the routine:
${\mathbf{ifail}}=1$
On entry, cb_handle does not define a valid handle to a NAG AD callback data object. It has not been initialized or has been corrupted.
${\mathbf{ifail}}=-99$
See Section 3.9 in How to Use the NAG Library and its Documentation for further information.
${\mathbf{ifail}}=-399$
Your licence key may have expired or may not have been installed correctly.
See Section 3.8 in How to Use the NAG Library and its Documentation for further information.
${\mathbf{ifail}}=-999$
Dynamic memory allocation failed.
See Section 3.7 in How to Use the NAG Library and its Documentation for further information.

Not applicable.

## 8Parallelism and Performance

x10bb_a1w_f is not threaded in any implementation.