PASCAL, Attributes, ASYNCHRONOUS
*Conan The Librarian
The ASYNCHRONOUS attribute indicates that a routine may be called by an asynchronous event (such as a condition handler). Since such an event can alter the values of variables within the routine upredictably, this attribute forces the routine to reference only local variables or variables declared with the VOLATILE attribute. See the "HP Pascal Language Reference Manual" for the complete description of using the ASYNCHRONOUS attribute.