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10.4. The system prelude and task list

10.4.1. The system prelude
The representation of the system-prelude is obtained from the following form, to which may be added further forms not defined in this Report. {The syntax of program-texts ensures that a declaration contained in the system-prelude may not contradict any declaration contained in the standard-prelude. It is intended that the further forms should contain declarations that are needed for the correct operation of any system-tasks that may be added (by the implementer, as provided in 10.1.2.d ).}

a) SEMA {?}gremlins =(SEMA s; {F}f OF s := PRIM INT := 0; s);

10.4.2. The system task list
The representation of the {first} constituent system-task or the system-task-list is obtained from the following form. The other system-tasks, if any, are not defined by this Report {but may be defined by the implementer in order to account for the particular features of his operating environment, especially in so far as they interact with the running of particular-programs (see, e.g., 10.3.1.1.dd )} .

DO DOWN gremlins; undefined; UP bfileprotect OD

{The intention is that this call of undefined, which is released by an UP gremlins whenever a book is closed, may reorganize the chain of backfiles and the chain of locked backfiles, such as by removing the book if it is not to be available for further opening, or by inserting it into the chain of backfiles several times over if it is to be permitted for several particular-programs to read it simultaneously. Note that, when an UP gremlins is given, bfileprotect is always down and remains so until such reorganization has taken place.}

{From ghoulies and ghosties and long-leggety beasties and things that go bump in the night. Good Lord, deliver us! Ancient Cornish litany}


 
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