add setjmp

c_expert/chapter6/setjmp_test.c

@@ -0,0 +1,23 @@
+#include <stdio.h>
+#include <setjmp.h>
+jmp_buf buf;
+
+
+void banana(void)
+{
+	printf("in banana() \n");
+	longjmp(buf, 1);
+	/* 一下代码不会被执行 */
+	printf("you'll never see this, because i longjmp'd");
+}
+
+int main(void)
+{
+	if (setjmp(buf)){
+		printf("back in main \n");
+	}else{
+		printf("first time throught\n");
+		banana();
+    }
+	return 0;
+}