diff --git a/Makefile b/Makefile
index 9c577e0..b87473f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 include Makefile.common
 
-all: k.iso
+all: bin k.iso
 
 k.iso: install
 	./tools/create_iso.sh
@@ -9,8 +9,16 @@ install:
 	mkdir -p $(GRUBDIR)
 	$(MAKE) -C $(SOURCEDIR) $@
 
+bin:
+	$(MAKE) -C $(LIB)
+	gcc -c test.c -Ilibk -Llibk -lk -m32
+	ld -m elf_i386 -Ttext=0x6000000 --entry=main test.o -L./libk/ -lk
+	objcopy --input binary --output elf32-i386 --binary-architecture i386 --rename-section .data=.rodata,CONTENTS,ALLOC,LOAD,READONLY,DATA a.out myfile.o
+	cp myfile.o $(SOURCEDIR)/myfile.o
+
 clean:
 	$(MAKE) -C $(SOURCEDIR) $@
+	$(MAKE) -C $(LIB) $@
 	$(RM) kernel.iso
 	$(RM) -r iso
 
diff --git a/Makefile.common b/Makefile.common
index 095aa11..92ed0b0 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -4,3 +4,4 @@ ASFLAGS = -m32
 GRUBDIR = iso
 SOURCEDIR = src
 TARGET = kernel
+LIB=libk
diff --git a/libk/Makefile b/libk/Makefile
new file mode 100644
index 0000000..15e0207
--- /dev/null
+++ b/libk/Makefile
@@ -0,0 +1,20 @@
+include ../Makefile.common
+
+
+OBJS	= \
+	  syscall.o \
+
+DEPS = $(OBJS:.o=.d)
+
+CPPFLAGS += -MMD -Iinclude
+CFLAGS += $(K_EXTRA_CFLAGS) -g -nostdlib
+LDFLAGS += -Wl,-Tkernel.lds
+LDLIBS =
+
+all: $(TARGET)
+	ar -rcs $(LIB).a *.o
+
+$(TARGET): $(OBJS)
+
+clean:
+	$(RM) $(OBJS) $(DEPS) $(TARGET) $(LIB).a
\ No newline at end of file
diff --git a/libk/syscall.c b/libk/syscall.c
new file mode 100644
index 0000000..aca3fae
--- /dev/null
+++ b/libk/syscall.c
@@ -0,0 +1,27 @@
+#include "syscall.h"
+
+int __syscall(int num, void *a0, void *a1, void *a2, void *a3, void *a4)
+{
+    int ret;
+    asm volatile("      \n \
+        mov %1, %%eax;  \n \
+        mov %2, %%ebx;  \n \
+        mov %3, %%ecx;  \n \
+        mov %4, %%edx;  \n \
+        mov %5, %%edi;  \n \
+        mov %6, %%esi;  \n \
+        int $48;        \n \
+        mov %%eax, %0" : "=m" (ret),
+                         "+m" (num),
+                         "+m" (a0),
+                         "+m" (a1),
+                         "+m" (a2),
+                         "+m" (a3),
+                         "+m" (a4));
+    return ret;
+}
+
+int write(int fd, char *buf, int count)
+{
+    return __syscall(1, (void *) fd, (void *) buf, (void *) count, (void *) 0, (void *) 0);
+}
diff --git a/libk/syscall.h b/libk/syscall.h
new file mode 100644
index 0000000..8c0bafc
--- /dev/null
+++ b/libk/syscall.h
@@ -0,0 +1,7 @@
+#ifndef SYSCALL_H
+#define SYSCALL_H
+
+int __syscall(int num, void *a0, void *a1, void *a2, void *a3, void *a4);
+int write(int fd, char *buf, int count);
+
+#endif  /*  !SYSCALL_H */
\ No newline at end of file
diff --git a/src/int.S b/src/int.S
index fbadc20..ef6f802 100644
--- a/src/int.S
+++ b/src/int.S
@@ -82,16 +82,24 @@ _asm_sycall_handler:
 	push %ds
 	push %es
 	push %fs
-	push %gs 
+	push %gs
 	push %ebx
 	mov $0x10,%bx
 	mov %bx,%ds
 	pop %ebx
+	push %esi
+	push %edi
+	push %edx
+	push %ecx
 	push %ebx
 	push %eax
     call syscall_handler
 	pop %ebx
 	pop %ebx
+	pop %ecx
+	pop %edx
+	pop %edi
+	pop %esi
     pop %gs
 	pop %fs
 	pop %es
diff --git a/src/isr.c b/src/isr.c
index 213950d..e3ea96c 100644
--- a/src/isr.c
+++ b/src/isr.c
@@ -28,16 +28,17 @@ void isr_kbd_int(void)
     DEBUG_INFO("Keyboard input: %d", x);
 }
 
-void syscall_handler(int eax, int ebx)
+int syscall_handler(int eax, void *ebx, void *ecx, void *edx, void *edi, void *esi)
 {
-    DEBUG_INFO("Syscall %d has been called from the userland with parameter %d", eax, ebx);
+    DEBUG_INFO("Syscall %d has been called from the userland with parameters: %d, %d, %d, %d, %d", eax, ebx, ecx, edx, edi, esi);
 
     switch (eax)
     {
     case 1:
-        char t = *((char *) ebx);
-        DEBUG_INFO("Syscall write : %d", (int) t);
-        return write(1, (u32) ebx);
+        int fd = (int) ebx;
+        char *buf = (char *) ecx;
+        int size = (int) edx;
+        return write(fd, buf, size);
         break;
     case 2:
         DEBUG_INFO("Syscall keyboard");
diff --git a/src/launch_process.c b/src/launch_process.c
index 2735335..18ca823 100644
--- a/src/launch_process.c
+++ b/src/launch_process.c
@@ -24,7 +24,7 @@ void launch_process(u16 tss, int memory_start, int userland_stack, int userland_
         movw %%ax, %%gs         \n \
         mov %%esp, %%eax         \n \
         push $0x23                 \n \
-        push $0x7FFFFFFF         \n \
+        push $0x7FFFEFFF         \n \
         pushfl                  \n \
         push $0x1B                 \n \
         push $0x6000000         \n \
diff --git a/src/myfile.o b/src/myfile.o
deleted file mode 100644
index 7cab458..0000000
Binary files a/src/myfile.o and /dev/null differ
diff --git a/src/syscall.c b/src/syscall.c
index 670f283..78f1150 100644
--- a/src/syscall.c
+++ b/src/syscall.c
@@ -6,9 +6,9 @@
  *  Syscall handler for write, currently only serial write is supported.
  *  Use the fd 1, to make a serial write.
  */
-int write(int fd, void *buf)
+int write(int fd, void *buf, int size)
 {
-    if (fd != 1)
+    if (fd != 1 || size < 0)
         return -1;
 
     if (write_serial(buf))
diff --git a/src/syscall.h b/src/syscall.h
index 36c9358..d69a768 100644
--- a/src/syscall.h
+++ b/src/syscall.h
@@ -1,7 +1,7 @@
 #ifndef SYSCALL_H
 #define SYSCALL_H
 
-int write(int fd, void *buf);
+int write(int fd, void *buf, int size);
 int keyboard(void);
 
 #endif /*   !SYSCALL_H */
\ No newline at end of file
diff --git a/src/userland.c b/src/userland.c
index edf2ed8..e154f90 100644
--- a/src/userland.c
+++ b/src/userland.c
@@ -20,6 +20,8 @@ int create_process(int uid, char *data_start)
 
     // Allocate stack
     allocate_new_page(uid, 0x7FFFF000);
+    allocate_new_page(uid, 0x7FFFE000);
+    allocate_new_page(uid, 0x7FFFD000);
 
     // TODO : create data seg by process
     // load elf