Two types of parameters can be altered. The first type is global to a process and not to a noticeboard (they are essentially Fortran COMMON block or C static variables). The second type is global to a noticeboard and are thus shared by all processes accessing that noticeboard. The original NBS_TUNE routine is used to alter parameters of the first type and the newer NBS_TUNE_NOTICEBOARD is used to tune parameters of the second type. When a noticeboard is created, its initial parameter values are copied from the current values of the first type.
When a parameter is altered, its previous value is returned and this permits a routine to alter a parameter, use the new value and then restore the parameter to its previous value.
The NBS_FIND, NBS_GET and NBS_PUT routines make rather complicated use of these values. For those parameters which are logical flags, they use the OR of the value of the first type and the value of the second type. For those parameters which are numeric values, they use the value of the first type.
- NBS_TUNE:
- Alter the value of a global parameter
- NBS_TUNE_NOTICEBOARD:
- Alter the value of a noticeboard-specific global parameter
NBS The Noticeboard System