diff --git a/src/interpreter/interpreter.rs b/src/interpreter/interpreter.rs
index 724866d..8962e08 100644
--- a/src/interpreter/interpreter.rs
+++ b/src/interpreter/interpreter.rs
@@ -18,6 +18,8 @@ use super::{
     interrupt::InterruptMessage,
 };
 
+const EINVAL: Word = 22;
+
 #[derive(Debug, Clone)]
 pub enum InterpreterError {
     InvalidSyscall(Byte),
@@ -787,18 +789,23 @@ impl Interpreter {
         }
 
         let msg = InterruptMessage::new(&data);
+        log::debug!("{msg}");
 
         // simulate interrupt handler code of MINIX
         match id {
             // sofware interrupts
             0x20 => {
-                log::debug!("Software interrupt with raw data {:?}", data);
+                log::debug!(
+                    "Software interrupt with raw data {:x?} of type {:#04x}",
+                    data,
+                    msg.m_type
+                );
                 match msg.m_type {
                     // EXIT()
                     0x01 => {
                         let data = Mess1::new(&data);
                         let status = data.i1;
-                        log::info!("executing exit({})", status);
+                        log::info!("<exit({})>", status);
                         exit(status.into())
                     }
                     // WRITE()
@@ -807,7 +814,7 @@ impl Interpreter {
                         let fd = data.i1;
                         let len = data.i2;
                         let location = data.p1;
-                        log::info!("executing write({}, {}, {})", fd, location, len);
+                        log::info!("<write({:#04x}, {:#04x}, {:#04x})>", fd, location, len);
                         for byte in &self.computer.memory.raw[location as usize..] {
                             if *byte == 0x00 {
                                 break;
@@ -815,6 +822,37 @@ impl Interpreter {
                                 print!("{}", *byte as char);
                             }
                         }
+
+                        // m_type response
+                        // TODO: save messages as pointer to remove this hack
+                        self.computer.write(len.into(), (bx + 2).into())?;
+                    }
+                    // TODO: BRK
+                    0x11 => {
+                        let bx = self.computer.regs.bx.read();
+                        let addr = self.computer.read((bx + 10).into())?;
+                        log::info!("<brk({:#04x})>", addr);
+
+                        // XXX add err handling?
+                        self.computer.write(addr.into(), (bx + 18).into())?;
+
+                        // m_type response
+                        // TODO: save messages as pointer to remove this hack
+                        self.computer
+                            .write(ImmediateOperand::Word(0), (bx + 2).into())?;
+                    }
+                    // IOCTL()
+                    0x36 => {
+                        let data = Mess2::new(&data);
+                        let tty = data.i1;
+                        let count = data.i3;
+                        let address = data.p1;
+                        log::info!("<ioctl({}, {}, {})>", tty, count, address);
+
+                        // m_type response
+                        // TODO: save messages as pointer to remove this hack
+                        let reply = (!EINVAL).wrapping_add(1);
+                        self.computer.write(reply.into(), (bx + 2).into())?;
                     }
                     _ => todo!(),
                 };
@@ -822,6 +860,11 @@ impl Interpreter {
             _ => return Err(InterpreterError::InvalidSyscall(id)),
         }
 
+        // XXX return val in AX?
+        self.computer
+            .regs
+            .write(crate::register::Register::AX, ImmediateOperand::Word(0));
+
         Ok(())
     }
 
diff --git a/src/interpreter/interrupt.rs b/src/interpreter/interrupt.rs
index 3544b37..6d62863 100644
--- a/src/interpreter/interrupt.rs
+++ b/src/interpreter/interrupt.rs
@@ -3,7 +3,6 @@ use core::fmt;
 use crate::operands::Word;
 
 // TODO:
-// typedef struct {int m2i1, m2i2, m2i3; long m2l1, m2l2; char *m2p1;} mess_2;
 // typedef struct {int m3i1, m3i2; char *m3p1; char m3ca1[M3_STRING];} mess_3;
 // typedef struct {long m4l1, m4l2, m4l3, m4l4, m4l5;} mess_4;
 // typedef struct {char m5c1, m5c2; int m5i1, m5i2; long m5l1, m5l2, m5l3;}mess_5;
@@ -22,7 +21,6 @@ pub struct Mess1 {
 
 impl Mess1 {
     pub fn new(data: &Vec<u8>) -> Self {
-        log::debug!("Mess1 from data {data:?}");
         Self {
             i1: Word::from_le_bytes([data[4], data[5]]),
             i2: Word::from_le_bytes([data[6], data[7]]),
@@ -43,6 +41,41 @@ impl fmt::Display for Mess1 {
         )
     }
 }
+
+#[derive(Debug, Clone)]
+// typedef struct {int m2i1, m2i2, m2i3; long m2l1, m2l2; char *m2p1;} mess_2;
+pub struct Mess2 {
+    pub i1: Word,
+    pub i2: Word,
+    pub i3: Word,
+    pub l1: Word,
+    pub l2: Word,
+    pub p1: Word,
+}
+
+impl Mess2 {
+    pub fn new(data: &Vec<u8>) -> Self {
+        Self {
+            i1: Word::from_le_bytes([data[4], data[5]]),
+            i2: Word::from_le_bytes([data[6], data[7]]),
+            i3: Word::from_le_bytes([data[8], data[9]]),
+            l1: Word::from_le_bytes([data[10], data[11]]),
+            l2: Word::from_le_bytes([data[12], data[13]]),
+            p1: Word::from_le_bytes([data[14], data[15]]),
+        }
+    }
+}
+
+impl fmt::Display for Mess2 {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "Mess1({} {} {} {} {} {})",
+            self.i1, self.i2, self.i3, self.l1, self.l2, self.p1
+        )
+    }
+}
+
 #[derive(Debug, Clone)]
 /// First part of: include/minix/type.h:struct message
 /// The union-type will be handled differently, where I the data of each