Follow ANSI standards (ie, C89 and X3J3/90.4 for C and
Fortran77, respectively) for maximum portability.
Be written as a subprogram (not a main) which returns an
integer status value.
(for C only) Contain the following block of code near the
top of the task subroutine:
#include "fitsio.h" /* assuming CFITSIO routines will be called */
#include "pil.h" /* assuming PIL routines will be called */
#define TOOLSUB my_task_subroutine_name /* use actual subroutine name here */
Check return status after all CFITSIO and PIL calls and
use the relevant error reporting routine if status is
Register a task name and version number (see below).