diff --git a/src/kernel/exception.rs b/src/kernel/exception.rs
index d920143..ee81ec2 100644
--- a/src/kernel/exception.rs
+++ b/src/kernel/exception.rs
@@ -3,7 +3,7 @@ use std::{cell::RefCell, rc::Rc};
 use crate::{simulator::{machine::{ExceptionType, Machine}, error::{MachineOk, MachineError}}};
 use crate::kernel::synch::{Lock, Semaphore};
 
-use super::{system::System, thread::Thread};
+use super::{system::{System, self}, thread::Thread};
 
 /// The halt system call. Stops Burritos.
 pub const SC_SHUTDOWN: u8 =	0;
@@ -142,7 +142,7 @@ fn syscall(machine: &mut Machine, system: &mut System) -> Result<MachineOk, Mach
             Ok(MachineOk::Ok)
         },
         SC_EXEC => todo!(),
-        SC_JOIN => todo!(),
+        SC_JOIN => sc_join(machine, system),
         SC_CREATE => todo!(),
         SC_OPEN => todo!(),
         SC_READ => todo!(),
@@ -231,7 +231,7 @@ fn sc_v(machine: &mut Machine, system: &mut System) -> Result<MachineOk, Machine
 fn sc_sem_create(machine: &mut Machine, system: &mut System) -> Result<MachineOk, MachineError> {
     let addr_name = machine.read_int_register(10) as usize;
     let initial_count = machine.read_int_register(11) as i32;
-    let size = get_length_param(addr_name as usize, machine);
+    let size = get_length_param(addr_name, machine);
     let _name = get_string_param(addr_name, size, machine);
     match initial_count < 0 {
         true => Err(format!("Initial_count < 0"))?,
@@ -262,6 +262,7 @@ fn sc_new_thread(machine: &mut Machine, system: &mut System) -> Result<MachineOk
 
     let n_thread = Thread::new(thread_name.as_str());
     let n_thread = Rc::new(RefCell::new(n_thread));
+    let tid = system.get_thread_manager().get_obj_addrs().add_thread(Rc::clone(&n_thread));
     let current_thread = match system.get_thread_manager().get_g_current_thread() {
         Some(th) => {
             Rc::clone(th)
@@ -274,25 +275,49 @@ fn sc_new_thread(machine: &mut Machine, system: &mut System) -> Result<MachineOk
     if let Some(process) = current_thread.get_process_owner() {
         system.get_thread_manager().start_thread(n_thread, Rc::clone(&process), func as u64, current_thread.thread_context.int_registers[2] as u64, args);
         // TODO changé la valeur de sp quand on supportera les addresses virtuels
-        // machine.write_fp_register(10, tid); // tid obtenu en faisant int32_t tid = g_object_addrs->AddObject(ptThread);
+        machine.write_int_register(10, tid as i64);
         Ok(MachineOk::Ok)
     } else {
         return Err("Process owner of current thread is none")?;
     }
 }
 
-fn get_length_param(addr: usize, machine: & Machine) -> usize{
+fn sc_join(machine: &mut Machine, system: &mut System) -> Result<MachineOk, MachineError> {
+    let tid = machine.read_int_register(10);
+    let p_thread = system.get_thread_manager().get_obj_addrs().search_thread(tid as i32);
+    match p_thread {
+        Some(_) => {
+            if let Some(current_thread) = system.get_thread_manager().get_g_current_thread() {
+                let rc = Rc::clone(current_thread);
+                system.get_thread_manager().thread_join(machine, rc);
+
+                Ok(MachineOk::Ok)
+            } else {
+                Ok(MachineOk::Ok)
+            }
+        },
+        None => {
+            // Thread already terminated (type set to INVALID_TYPE) or call on an object
+	        // that is not a thread
+	        // Exit with no error code since we cannot separate the two cases
+            Ok(MachineOk::Ok)
+        }
+    }
+}
+
+fn get_length_param(addr: usize, machine: & Machine) -> usize {
     let mut i = 0;
     let mut c = 1;
-    while c!= 0 {
+    while c != 0 {
         c = machine.read_memory(1, addr + i);
-        i+=1;
+        i +=1;
 
     }
+    println!("addr: {:x}, i: {}", addr, i + 1);
     i + 1
 }
 
-fn get_string_param(addr: usize, maxlen: usize, machine: &Machine) -> Vec<char>{
+fn get_string_param(addr: usize, maxlen: usize, machine: &Machine) -> Vec<char> {
     let mut dest = Vec::with_capacity(maxlen);
 
     let mut i: usize = 0;
@@ -300,12 +325,10 @@ fn get_string_param(addr: usize, maxlen: usize, machine: &Machine) -> Vec<char>{
 
     while c != 0 && i < maxlen {
         c = machine.read_memory(1, addr + i) as u8;
-        //dest.push(c as char);
-        dest[i] = c as char;
+        dest.push(c as char);
         i += 1;
     }
-
-    dest[maxlen - 1] = '\0';
+    dest.push('\0');
 
     dest
 }
diff --git a/src/main.rs b/src/main.rs
index 5de60b9..bc9b050 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -40,7 +40,7 @@ fn main() {
     let args = Args::parse();
 
     let mut machine = Machine::new(args.debug);
-    let (loader, ptr) = loader::Loader::new(args.executable.as_str(), &mut machine, 0).expect("IO Error");
+    let (loader, ptr) = loader::Loader::new(args.executable.as_str(), &mut machine, 0).expect("An error occured while parsing the program");
     
     let mut system = System::default();
 
diff --git a/src/simulator/loader.rs b/src/simulator/loader.rs
index 3239cab..0820a4c 100644
--- a/src/simulator/loader.rs
+++ b/src/simulator/loader.rs
@@ -213,23 +213,23 @@ impl ElfHeader {
 }
 
 impl TryFrom<&Vec<u8>> for ElfHeader {
-    type Error = ();
+    type Error = String;
 
     fn try_from(instructions: &Vec<u8>) -> Result<Self, Self::Error> {
         if Self::is_elf(instructions) {
             let format = Self::is_32bits(instructions);
             let endianess = Self::check_endianess(instructions);
-            let version = Self::get_version(instructions).ok_or(())?;
+            let version = Self::get_version(instructions).ok_or("Cannot retrieve version")?;
             let is_sys_v_abi = Self::is_system_v_elf(instructions);
             let is_rv_target = Self::is_riscv_isa(instructions);
-            let entrypoint = Self::get_entrypoint(instructions, format).ok_or(())?;
-            let elf_header_size = Self::get_elf_header_size(instructions, format).ok_or(())?;
-            let program_header_location = Self::get_program_header_table_location(instructions, format).ok_or(())?;
-            let program_header_entries = Self::get_number_entries_program_header(instructions, format).ok_or(())? ;
-            let program_header_size = Self::get_program_header_size(instructions, format).ok_or(())?;
-            let section_header_location = Self::get_section_header_table_location(instructions, format).ok_or(())?;
-            let section_header_entries = Self::get_section_header_num_entries(instructions, format).ok_or(())?;
-            let section_header_size = Self::get_section_header_size(instructions, format).ok_or(())?;
+            let entrypoint = Self::get_entrypoint(instructions, format).ok_or("Cannot get entrypoint")?;
+            let elf_header_size = Self::get_elf_header_size(instructions, format).ok_or("Cannot get elf header size")?;
+            let program_header_location = Self::get_program_header_table_location(instructions, format).ok_or("Cannot get program header table location")?;
+            let program_header_entries = Self::get_number_entries_program_header(instructions, format).ok_or("Cannot get number of entries in program header table")? ;
+            let program_header_size = Self::get_program_header_size(instructions, format).ok_or("Cannot get program header entry size")?;
+            let section_header_location = Self::get_section_header_table_location(instructions, format).ok_or("Cannot get section header table location")?;
+            let section_header_entries = Self::get_section_header_num_entries(instructions, format).ok_or("Cannot get number of entries of section header")?;
+            let section_header_size = Self::get_section_header_size(instructions, format).ok_or("Cannot get size of section header entry")?;
             Ok(ElfHeader { 
                 endianess, 
                 is_32bits: format,
@@ -246,7 +246,7 @@ impl TryFrom<&Vec<u8>> for ElfHeader {
                 section_header_size
             })
         } else {
-            Err(())
+            Err("File doesn't have elf magic number")?
         }
     }
 }
@@ -409,7 +409,7 @@ pub enum LoaderError {
     /// Correspond to std IO error
     IOError(std::io::Error),
     /// Others errors
-    ParsingError
+    ParsingError(String)
 }
 
 /// Global structure of the loader, one instance per loaded files
@@ -455,7 +455,13 @@ impl Loader {
                     let mut buf: [u8; 4] = [0; 4];
                     #[allow(clippy::needless_range_loop)]
                     for k in 0..buf.len() {
-                        buf[k] = self.bytes.get(section.image_offset as usize + j + k).copied().ok_or(LoaderError::ParsingError)?;
+                        if section.does_flag_contains_key(FlagValue::ShfWrite) {
+                            // flag WA, on doit allouer des données initialisés à 0
+                            // généralement, ce signifie que le compilateur à ajouter une section .bss
+                            buf[k] = 0;
+                        } else {
+                            buf[k] = self.bytes.get(section.image_offset as usize + j + k).copied().ok_or(LoaderError::ParsingError(format!("index 0x{:x} is out of bound because list have a size of 0x{:x} (image offset 0x{:x}, j 0x{:x}, k 0x{:x})", section.image_offset as usize + j + k, self.bytes.len(), section.image_offset, j, k)))?;
+                        }
                     }
                     machine.write_memory(4, start_index + section.virt_addr as usize + j, u32::from_le_bytes(buf) as u64);
                 }
@@ -492,8 +498,8 @@ impl Loader {
                     Ok(header) => {
                         header
                     },
-                    Err(_) => {
-                        return Err(LoaderError::ParsingError);
+                    Err(err) => {
+                        return Err(LoaderError::ParsingError(format!("Cannot parse elf header : {}", err)));
                     }
                 };
                 let section_header = match Self::parse_section_header(&instructions, elf_header.is_32bits, elf_header.section_header_location, elf_header.section_header_entries, elf_header.section_header_size) {
@@ -501,7 +507,7 @@ impl Loader {
                         header
                     },
                     Err(_) => {
-                        return Err(LoaderError::ParsingError);
+                        return Err(LoaderError::ParsingError("Cannot parse section header".to_string()));
                     }
                 };
                 // #[cfg(debug_assertions)]
diff --git a/src/utility/objaddr.rs b/src/utility/objaddr.rs
index 33f17dd..e788eb0 100644
--- a/src/utility/objaddr.rs
+++ b/src/utility/objaddr.rs
@@ -2,9 +2,9 @@
 //! their references. The ObjAddr struct
 //! allows to maintain this data structure.
 
-use std::collections::HashMap;
+use std::{collections::HashMap, cell::RefCell, rc::Rc};
 
-use crate::kernel::synch::{ Semaphore, Lock };
+use crate::kernel::{synch::{ Semaphore, Lock }, thread::Thread};
 
 /// Brief Definition of object identifiers:
 /// 
@@ -19,7 +19,8 @@ use crate::kernel::synch::{ Semaphore, Lock };
 pub struct ObjAddr {
     last_id: i32,
     semaphores: HashMap<i32, Semaphore>,
-    locks: HashMap<i32, Lock>
+    locks: HashMap<i32, Lock>,
+    threads: HashMap<i32, Rc<RefCell<Thread>>>,
 }
 
 impl ObjAddr {
@@ -29,7 +30,8 @@ impl ObjAddr {
         Self {
             last_id: 3,
             semaphores: HashMap::<i32, Semaphore>::new(),
-            locks: HashMap::<i32, Lock>::new()
+            locks: HashMap::<i32, Lock>::new(),
+            threads: HashMap::<i32, Rc<RefCell<Thread>>>::new(),
         }
     }
 
@@ -47,6 +49,13 @@ impl ObjAddr {
         self.last_id
     }
 
+    /// Adds the **obj** Lock to self
+    pub fn add_thread(&mut self, obj: Rc<RefCell<Thread>>) -> i32 {
+        self.last_id +=1;
+        self.threads.insert(self.last_id, obj);
+        self.last_id
+    }
+
     /// Searches for a semaphore of id **id** in self
     pub fn search_semaphore(&mut self, id: i32) -> Option<&mut Semaphore> {
         self.semaphores.get_mut(&id)
@@ -57,6 +66,11 @@ impl ObjAddr {
         self.locks.get_mut(&id)
     }
 
+    /// Searches for a lock of id **id** in self
+    pub fn search_thread(&mut self, id: i32) -> Option<&Rc<RefCell<Thread>>> {
+        self.threads.get(&id)
+    }
+
     /// Removes the object of id **id** from self if it exists
     pub fn remove_semaphore(&mut self, id: i32) -> Option<Semaphore> {
         self.semaphores.remove(&id)
@@ -67,5 +81,10 @@ impl ObjAddr {
         self.locks.remove(&id)
     }
 
+    /// Remove the object of id **id** from self if it exists
+    pub fn remove_thread(&mut self, id: i32) -> Option<Rc<RefCell<Thread>>> {
+        self.threads.remove(&id)
+    }
+
 
 }
\ No newline at end of file
diff --git a/test/syscall_tests/Makefile b/test/syscall_tests/Makefile
index c374c49..8388949 100644
--- a/test/syscall_tests/Makefile
+++ b/test/syscall_tests/Makefile
@@ -1,4 +1,4 @@
-PROGRAMS = halt.guac prints.guac
+PROGRAMS = halt.guac prints.guac producteur_consommateur.guac
 TOPDIR = ../..
 include $(TOPDIR)/Makefile.rules
 
diff --git a/test/syscall_tests/producteur_consommateur.c b/test/syscall_tests/producteur_consommateur.c
new file mode 100644
index 0000000..f0126cb
--- /dev/null
+++ b/test/syscall_tests/producteur_consommateur.c
@@ -0,0 +1,48 @@
+#include "userlib/syscall.h"
+#include "userlib/libnachos.h"
+
+
+const int N = 3;
+int iplein = 0;
+int ivide = 0;
+int tab[3];
+SemId svide;
+SemId splein;
+
+void producteur();
+
+void consommateur();
+
+int main() {
+    svide = SemCreate("producteur", N);
+    splein = SemCreate("consommateur", 0);
+    ThreadId producteurTh = threadCreate("producteur", producteur);
+    ThreadId consommateurTh = threadCreate("consommateur", consommateur);
+    Join(producteurTh);
+    Join(consommateurTh);
+    return 0;
+}
+
+void producteur() {
+    for(int i = 0; i < 10; i++) 
+    {
+        n_printf("batir une information\n");
+        P(svide);
+        iplein = (iplein + 1) % N;
+        n_printf("communique une information : %d\n", i);
+        tab[iplein] = i;
+        V(splein);
+    }
+}
+
+void consommateur() {
+    for(int i = 0; i < 10; i++) 
+    {
+        P(splein);
+        ivide = (ivide +1) % N;
+        n_printf("recevoir une information\n");
+        int info = tab[ivide];
+        V(svide);
+        n_printf("exploiter l'information : %d\n", info);
+    }
+}