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--- c:setjmp.h:longjmp [2013/02/03 19:14]
127.0.0.1 external edit
+++ c:setjmp.h:longjmp [2024/02/16 01:05] (current)
@@ Line 1: / Line 1: @@
 ====== longjmp ======
 <code c>
+void longjmp (jmp_buf env, int val);
 </code>
 ==== description of longjmp ====
-longjmp is in work by code-reference.com \\
+get program state from the stack, useful for debugging.
-if you are faster... don't hasitate and add it
 <code c>
-no example at the moment
+#include <stdio.h>
+#include <setjmp.h>
+void testit(int);
+jmp_buf program_state;
+static int count;
+void testit(int count) {
+   count++; // set counter +1 but it will never reach 2
+   printf("count is now %i\n", count);
+   }
+int main(void) {
+   count = 0;
+   printf("count starts with: %i\n", count);
+   if(setjmp(program_state) == 0) {
+       printf("save program state in the stack\n");
+       testit(count);
+   }
+   else {
+        printf("callback with longjmp\n");
+        testit(count);
+        testit(count);
+        return 0;
+   }
+   testit(count);
+   longjmp(program_state,1);
+   printf("never called\n");
+   testit(count);
+   return 0;
+}
 </code>
 ===== output of longjmp c example =====
-    no example at the moment
+    count starts with: 0
+    save program state in the stack
+    count is now 1
+    count is now 1
+    callback with longjmp
+    count is now 1
+    count is now 1

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