36 lines
892 B
Modula-2
36 lines
892 B
Modula-2
DEFINITION MODULE Processes;
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(*
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Module: Processes
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From: "Programming in Modula-2", 3rd, corrected edition, by N. Wirth
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Version: $Header$
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*)
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(*
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As discussed in "Unfair Process Scheduling in Modula-2", by
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D. Hemmendinger, SIGplan Notices Volume 23 nr 3, march 1988,
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the scheduler in this module is unfair, in that in some circumstances
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ready-to-run processes never get a turn.
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*)
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TYPE SIGNAL;
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PROCEDURE StartProcess(P: PROC; n: CARDINAL);
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(* Start a concurrent process with program "P" and workspace of
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size "n"
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*)
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PROCEDURE SEND(VAR s: SIGNAL);
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(* One process waiting for "s" is resumed
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*)
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PROCEDURE WAIT(VAR s: SIGNAL);
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(* Wait for some other process to send "s"
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*)
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PROCEDURE Awaited(s: SIGNAL): BOOLEAN;
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(* Return TRUE if at least one process is waiting for sinal "s".
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*)
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PROCEDURE Init(VAR s: SIGNAL);
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(* Compulsory initialization
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*)
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END Processes.
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