39 lines
1.1 KiB
Modula-2
39 lines
1.1 KiB
Modula-2
DEFINITION MODULE Traps;
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(*
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Module: Facility for handling traps
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Author: Ceriel J.H. Jacobs
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Version: $Header$
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*)
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IMPORT EM;
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CONST
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ERRTOOLARGE = 64; (* stack size of process too large *)
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ERRTOOMANY = 65; (* too many nested traps + handlers *)
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ERRNORESULT = 66; (* no RETURN from function procedure *)
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ERRCARDOVFL = 67; (* CARDINAL overflow *)
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ERRFORLOOP = 68; (* value of FOR-loop control variable changed
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in loop
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*)
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ERRCARDUVFL = 69; (* CARDINAL underflow *)
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ERRINTERNAL = 70; (* Internal error; should not happen *)
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TYPE TrapHandler = EM.TrapHandler;
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PROCEDURE InstallTrapHandler(t: TrapHandler): TrapHandler;
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(* Install a new trap handler, and return the previous one.
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Parameter of trap handler is the trap number.
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When a trap occurs, the default trap handler is re-installed before
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calling the new handler.
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*)
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PROCEDURE Message(str: ARRAY OF CHAR);
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(* Write message "str" on standard error, preceeded by filename and
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linenumber if possible
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*)
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PROCEDURE Trap(n: INTEGER);
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(* cause trap number "n" to occur *)
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END Traps.
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