diff --git a/mers_lib/Cargo.toml b/mers_lib/Cargo.toml
index 70fe203..ece12c9 100755
--- a/mers_lib/Cargo.toml
+++ b/mers_lib/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "mers_lib"
-version = "0.9.11"
+version = "0.9.12"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "library to use the mers language in other projects"
diff --git a/mers_lib/src/program/configs/with_stdio.rs b/mers_lib/src/program/configs/with_stdio.rs
index 5010a75..213a9be 100755
--- a/mers_lib/src/program/configs/with_stdio.rs
+++ b/mers_lib/src/program/configs/with_stdio.rs
@@ -14,7 +14,7 @@ use crate::{
 
 use super::{
     gen::{
-        function::{func, func_end},
+        function::{func, func_err},
         IntR, OneOrNone,
     },
     Config,
@@ -60,8 +60,15 @@ impl Config {
             // )
             .add_var(
                 "exit",
-                func_end(|code: IntR<INT_MIN, INT_MAX>, _| {
-                    std::process::exit(code.0.try_into().unwrap_or(255));
+                func_err(|code: IntR<INT_MIN, INT_MAX>, i| {
+                    if i.global
+                        .allow_process_exit_via_exit
+                        .load(std::sync::atomic::Ordering::Relaxed)
+                    {
+                        std::process::exit(code.0.try_into().unwrap_or(255));
+                    } else {
+                        format!("Program exited with status code {}", code.0).into()
+                    }
                 }),
             )
             .add_var(
diff --git a/mers_lib/src/program/run/mod.rs b/mers_lib/src/program/run/mod.rs
index 10832c6..0a6a149 100755
--- a/mers_lib/src/program/run/mod.rs
+++ b/mers_lib/src/program/run/mod.rs
@@ -2,7 +2,7 @@ use std::{
     collections::HashMap,
     fmt::Debug,
     io::{Read, Write},
-    sync::{Arc, Mutex, RwLock},
+    sync::{atomic::AtomicBool, Arc, Mutex, RwLock},
     time::Instant,
 };
 
@@ -135,6 +135,7 @@ pub struct RunLocalGlobalInfo {
     pub object_fields_rev: Arc<Mutex<Vec<String>>>,
     pub stdin: Arc<Mutex<Option<Box<dyn Read + Send + Sync>>>>,
     pub stdout: Arc<Mutex<Option<(Box<dyn Write + Send + Sync>, Box<dyn Write + Send + Sync>)>>>,
+    pub allow_process_exit_via_exit: Arc<AtomicBool>,
 }
 #[derive(Debug)]
 #[allow(unused)]
@@ -144,6 +145,7 @@ struct RunLocalGlobalInfoDebug<'a> {
     pub object_fields_rev: &'a Arc<Mutex<Vec<String>>>,
     pub stdin: bool,
     pub stdout: bool,
+    pub allow_process_exit_via_exit: bool,
 }
 impl Debug for RunLocalGlobalInfo {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
@@ -155,7 +157,10 @@ impl Debug for RunLocalGlobalInfo {
                 object_fields: &self.object_fields,
                 object_fields_rev: &self.object_fields_rev,
                 stdin: self.stdin.lock().unwrap().is_some(),
-                stdout: self.stdout.lock().unwrap().is_some()
+                stdout: self.stdout.lock().unwrap().is_some(),
+                allow_process_exit_via_exit: self
+                    .allow_process_exit_via_exit
+                    .load(std::sync::atomic::Ordering::Relaxed),
             }
         )
     }
@@ -168,6 +173,7 @@ impl RunLocalGlobalInfo {
             object_fields_rev: Default::default(),
             stdin: Arc::new(Mutex::new(None)),
             stdout: Arc::new(Mutex::new(None)),
+            allow_process_exit_via_exit: Arc::new(AtomicBool::new(true)),
         }
     }
 }
@@ -247,6 +253,7 @@ impl info::Local for RunLocal {
             object_fields_rev: Default::default(),
             stdin: Default::default(),
             stdout: Default::default(),
+            allow_process_exit_via_exit: Arc::new(AtomicBool::new(false)),
         }
     }
     fn init_var(&mut self, id: Self::VariableIdentifier, value: Self::VariableData) {