| 1 | /* Introduction to Non-Local Exits |
|---|
| 2 | Copyright (C) 1991-2022 Free Software Foundation, Inc. |
|---|
| 3 | |
|---|
| 4 | This program is free software; you can redistribute it and/or |
|---|
| 5 | modify it under the terms of the GNU General Public License |
|---|
| 6 | as published by the Free Software Foundation; either version 2 |
|---|
| 7 | of the License, or (at your option) any later version. |
|---|
| 8 | |
|---|
| 9 | This program is distributed in the hope that it will be useful, |
|---|
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
|---|
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
|---|
| 12 | GNU General Public License for more details. |
|---|
| 13 | |
|---|
| 14 | You should have received a copy of the GNU General Public License |
|---|
| 15 | along with this program; if not, see <https://www.gnu.org/licenses/>. |
|---|
| 16 | */ |
|---|
| 17 | |
|---|
| 18 | #include <setjmp.h> |
|---|
| 19 | #include <stdlib.h> |
|---|
| 20 | #include <stdio.h> |
|---|
| 21 | |
|---|
| 22 | jmp_buf main_loop; |
|---|
| 23 | |
|---|
| 24 | void |
|---|
| 25 | abort_to_main_loop (int status) |
|---|
| 26 | { |
|---|
| 27 | longjmp (env: main_loop, val: status); |
|---|
| 28 | } |
|---|
| 29 | |
|---|
| 30 | int |
|---|
| 31 | main (void) |
|---|
| 32 | { |
|---|
| 33 | while (1) |
|---|
| 34 | if (setjmp (main_loop)) |
|---|
| 35 | puts (s: "Back at main loop...." ); |
|---|
| 36 | else |
|---|
| 37 | do_command (); |
|---|
| 38 | } |
|---|
| 39 | |
|---|
| 40 | |
|---|
| 41 | void |
|---|
| 42 | do_command (void) |
|---|
| 43 | { |
|---|
| 44 | char buffer[128]; |
|---|
| 45 | if (fgets (s: buffer, n: 128, stdin) == NULL) |
|---|
| 46 | abort_to_main_loop (status: -1); |
|---|
| 47 | else |
|---|
| 48 | exit (EXIT_SUCCESS); |
|---|
| 49 | } |
|---|
| 50 | |
|---|
