diff --git a/Makefile b/Makefile
index eda4420..5b50d53 100644
--- a/Makefile
+++ b/Makefile
@@ -4,6 +4,9 @@ SRC = \
 	ft_strlen.s \
 	ft_strcpy.s \
 	ft_strcmp.s \
+	ft_write.s \
+	ft_read.s \
+	ft_strdup.s \
 
 OBJ = $(SRC:.s=.o)
 
@@ -16,7 +19,7 @@ $(NAME): $(OBJ)
 	ar rcs libasm.a $(OBJ)
 
 test: $(NAME)
-	gcc -Wall -Werror -Wextra -g main.c -L. -lasm -o libasm_unit_tests
+	gcc -Wall -Werror -Wextra -no-pie -g main.c -lc -L. -lasm -o libasm_unit_tests
 
 clean:
 	rm $(OBJ)
diff --git a/ft_read.s b/ft_read.s
new file mode 100644
index 0000000..d434b3c
--- /dev/null
+++ b/ft_read.s
@@ -0,0 +1,21 @@
+extern __errno_location
+
+section .text
+	global ft_read
+
+ft_read:
+	mov rax, 0 ; syscall read, other arguments should be good accord to calling convention
+	syscall
+	cmp eax, -1 ; linux syscalls errors are always in the range -4095 to -1
+	jg .done
+	cmp eax, -4095
+	jl .done
+	mov rbx, rax ; save return value of syscall
+	call __errno_location ; put address of errno in rax
+	neg rbx ; errno should be positive
+	mov [rax], rbx ; set errno
+	mov rax, -1 ; set return value of ft_read to -1
+	ret
+
+.done:
+	ret
diff --git a/ft_strcmp.s b/ft_strcmp.s
index 99f718f..2e7fc6a 100644
--- a/ft_strcmp.s
+++ b/ft_strcmp.s
@@ -12,8 +12,8 @@ ft_strcmp:
 	inc rdx
 	jmp .loop
 .done:
-	movsx rax, byte [rdi + rdx]
-	movsx rbx, byte [rsi + rdx]
+	mov al, byte [rdi + rdx]
+	mov bl, byte [rsi + rdx]
 	sub rax, rbx
 	ret
 
diff --git a/ft_strcpy.s b/ft_strcpy.s
index ce98d48..0c75a75 100644
--- a/ft_strcpy.s
+++ b/ft_strcpy.s
@@ -10,7 +10,6 @@ ft_strcpy:
 	inc rax
 	jmp .loop
 .done:
-	inc rax
 	mov byte [rdi + rax], 0
 	mov rax, rdi 
 	ret
diff --git a/ft_strdup.s b/ft_strdup.s
new file mode 100644
index 0000000..68ac018
--- /dev/null
+++ b/ft_strdup.s
@@ -0,0 +1,25 @@
+global ft_strdup
+
+extern my_test
+extern malloc
+extern ft_strlen
+extern ft_strcpy
+
+ft_strdup:
+	enter 16, 0
+	push rdi
+	enter 16, 0
+	call ft_strlen
+	mov rdi, rax
+	inc rdi
+	call malloc
+	cmp rax, 0
+	jz .done
+	leave
+	mov rdi, rax
+	pop rsi
+	call ft_strcpy
+
+.done:
+	leave
+	ret
diff --git a/ft_write.s b/ft_write.s
new file mode 100644
index 0000000..0ef58c4
--- /dev/null
+++ b/ft_write.s
@@ -0,0 +1,21 @@
+extern __errno_location
+
+section .text
+	global ft_write
+
+ft_write:
+	mov rax, 1 ; syscall write, other arguments should be good accord to calling convention
+	syscall
+	cmp eax, -1 ; linux syscalls errors are always in the range -4095 to -1
+	jg .done
+	cmp eax, -4095
+	jl .done
+	mov rbx, rax ; save return value of syscall
+	call __errno_location ; put address of errno in rax
+	neg rbx ; errno should be positive
+	mov [rax], rbx ; set errno
+	mov rax, -1 ; set return value of ft_write to -1
+	ret
+
+.done:
+	ret
diff --git a/libasm.h b/libasm.h
index c4bf3cc..4f1dcb6 100644
--- a/libasm.h
+++ b/libasm.h
@@ -2,9 +2,14 @@
 # define _LIBASM_H
 
 #include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
 
 size_t ft_strlen(const char *);
 char *ft_strcpy(char *, const char *);
 int ft_strcmp(const char *, const char *);
+ssize_t ft_write(int, const void *, size_t);
+ssize_t ft_read(int, void *, size_t);
+char *ft_strdup(const char *);
 
 #endif
diff --git a/main.c b/main.c
index ee9eaf4..0f61ff4 100644
--- a/main.c
+++ b/main.c
@@ -1,26 +1,53 @@
 #include "libasm.h"
+#include <string.h>
 #include <stdlib.h>
+#include <errno.h>
+
+void my_test(void) {
+	write(1, "Hello, world!\n", 14);
+	printf("Hello, world!\n");
+}
+
+void *my_malloc(size_t size) {
+	printf("CALLLLLLED\n");
+	fflush(stdout);
+	printf("called with size %ld\n", size);
+	fflush(stdout);
+	printf("222323\n");
+	fflush(stdout);
+	return malloc(size);
+}
+
 
 int main() {
-	char my_string[37] = "c'est moi la chaine de 36 caracteres"; 
-	printf("%ld\n", ft_strlen(my_string));
+/*	char *str1 = (char *)malloc(88 * sizeof(char));
+	ft_strcpy(str1, "Salut moi une chaine de caractere trop longue\n");
+	printf("%ld\n", ft_write(1, str1, 46));
+	printf("%d\n", (int)str1[0]);
+	free(str1);
 
-	char *str;
-	str = (char *)malloc(150 * sizeof(char));
-	str = "Salut c'est moi la zone mdr\0";
-	char *dst;
-	dst = (char *)malloc(50 * sizeof(char));
-	char *test = ft_strcpy(dst, str);
-	printf("%s\n", str);
-	printf("%s\n", dst);
-	printf("%s\n", test);
-	printf("should be 0: %d\n", ft_strcmp(str, dst));
-	printf("should be 0 and not segv: %d\n", ft_strcmp(dst, test));
-	printf("should be 16 %d\n", ft_strcmp(my_string, str));
-	printf("should be -16 %d\n", ft_strcmp(str, my_string));
-	dst = "Salut c'est moi la diff mdr\0";
-	printf("should be 22: %d\n", ft_strcmp(str, dst));
-	dst = "Salut\0 c'est moi la diff mdr\0";
-	printf("should be 32: %d\n", ft_strcmp(str, dst));
+	char *str2 = (char *)malloc(88 * sizeof(char));
+	strcpy(str2, "Salut moi une chaine de caractere trop longue\n");
+	printf("%ld\n", write(1, str2, 46));
+	printf("%d\n", (int)str2[0]);
+	free(str2);
+
+	ssize_t write_ret = write(4, "test\n", 5);
+	if (write_ret == -1) {
+		fprintf(stderr, "error = %s\n", strerror(errno));
+		perror("write");
+	}
+	errno = 42;
+	write_ret = ft_write(4, "test\n", 5);
+	printf("ft_write ret %ld\n", write_ret);
+	if (write_ret == -1) {
+		fprintf(stderr, "error = %d\n", errno);
+		fprintf(stderr, "error = %s\n", strerror(errno));
+		perror("ft_write");
+	}*/
+	char *str = ft_strdup("Salut c'est moi libasm\n");
+	ft_write(1, "Hello, world!\n", 14);
+	printf("len %ld\n", ft_strlen(str));
+	ft_write(1, str, ft_strlen(str));
 	return 0;
 }