From 2928bd9fd95eef2191188b8346151bdb058cd2bf Mon Sep 17 00:00:00 2001
From: kumail074 <kumail074@proton.me>
Date: Sat, 23 Nov 2024 01:12:13 +0500
Subject: [PATCH] longjmp

---
 learning/processes/longjmp.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 learning/processes/longjmp.c

diff --git a/learning/processes/longjmp.c b/learning/processes/longjmp.c
new file mode 100644
index 0000000..aaf2f2f
--- /dev/null
+++ b/learning/processes/longjmp.c
@@ -0,0 +1,32 @@
+#include <tlpi.h>
+#include <setjmp.h>
+
+static jmp_buf env;
+
+static void f2(void) {
+    longjmp(env, 2);
+}
+
+static void f1(int argc) {
+    if(argc == 1)
+        longjmp(env, 1);
+    f2();
+}
+
+int main(int argc, char *argv[]) {
+    switch (setjmp(env)) {
+        case 0:
+            printf("calling f1() after initial setjmp()\n");
+            f1(argc);
+            break;
+
+        case 1:
+            printf("came back from f1()\n");
+            break;
+
+        case 2:
+            printf("came back from f2()\n");
+            break;
+        }
+    exit(EXIT_SUCCESS);
+}