AddExitProc: what changed

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Title: AddExitProc

New		Line
1	+	## AddExitProc
2	+
3	+	With AddExitProc, you can assign a procedure that is called when the program ends; even when terminated by a runtime error.
4	+
5	+	Compared to the simple [[ExitProc]], this has the advantage that you don't have to worry about saving and calling up the old ExitProc, this happens automatically in the background with AddExitProc.
6	+
7	+	In this example, a file that does not exist is deliberately opened:
8	+
9	+	``` pascal
10	+	program AddExitProc_Example;
11	+
12	+	const
13	+	MyExitCode = 123;
14	+
15	+	procedure end;
16	+	begin
17	+	WriteLn('This is the end');
18	+
19	+	case ExitCode of
20	+	2:
21	+	begin
22	+	WriteLn('file not found');
23	+	end;
24	+
25	+	MyExitCode:
26	+	begin
27	+	WriteLn('It was deliberately terminated with ', MyExitCode);
28	+	end;
29	+	else
30	+	begin
31	+	WriteLn('Error: ', ExitCode);
32	+	end;
33	+	end;
34	+	end;
35	+
36	+	var
37	+	f : file;
38	+
39	+	begin
40	+	// Assign new ExitProc
41	+	AddExitProc(@end);
42	+
43	+	// Open a file that doesn't exist
44	+	Assign(f, 'abc.txt');
45	+
46	+	// This triggers runtime error 2
47	+	Reset(f);
48	+
49	+	// Cancel with your own code.
50	+	Halt(MyExitCode);
51	+	end.
52	+	```
53	+
54	+	## See also
55	+
56	+	- [[ExitProc]] and [[ExitProc\|ExitCode]] - intercept the end of the program and evaluate ExitCode.
57	+
58	+	---
59	+	From the Free Pascal wiki, page "AddExitProc", as it stood on 2020-05-19 after a change by FTurtle, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).