diff --git a/README.md b/README.md
new file mode 100644
index 0000000..e45aa7b
--- /dev/null
+++ b/README.md
@@ -0,0 +1,17 @@
+# tlibc
+C library with collections, strings, exceptions, io...
+
+
+## Build
+1. Clone the repository.
+    ```
+    git clone https://timerix.ddns.net/git/Timerix/tlibc.git
+    ```
+2. Install [cbuild](https://timerix.ddns.net/git/Timerix/cbuild.git).
+3. Build static library
+    ```
+    cd tlibtoml
+    cbuild build_static_lib_dbg
+    ```
+
+## Usage
diff --git a/include/tlibc/errors.h b/include/tlibc/errors.h
index 4fcc778..4c33dcd 100755
--- a/include/tlibc/errors.h
+++ b/include/tlibc/errors.h
@@ -18,15 +18,31 @@ typedef struct ErrorCallPos {
 typedef struct Error {
     str msg;
     bool is_msg_on_heap;
+    u16 error_code_page;
+    u32 error_code;
     List(ErrorCallPos) call_stack;
 } Error;
 
-Error* Error_create(const char* msg, bool is_msg_on_heap, ErrorCallPos p);
+Error* Error_create(const char* msg, bool is_msg_on_heap, ErrorCallPos p,
+    u16 error_code_page, u32 error_code);
 void Error_free(Error* e);
 void Error_addCallPos(Error* e, ErrorCallPos p);
 str Error_toStr(Error* e);
 void Error_printAndExit(Error* e) ATTRIBUTE_NORETURN;
 
+#define ErrorCodePage_name(name) ErrorCodePage_##name
+#define ErrorCodePage_declare(name) extern u16 ErrorCodePage_name(name);
+#define ErrorCodePage_define(name) u16 ErrorCodePage_name(name) = 0;
+void _ErrorCodePage_register(u16* error_code_page_ptr);
+#define ErrorCodePage_register(name) _ErrorCodePage_register(&ErrorCodePage_name(name));
+
+typedef enum TLIBC_ERROR {
+    TLIBC_ERROR_UNKNOWN
+} TLIBC_ERROR;
+#define ErrorCodePage_NONE 0
+ErrorCodePage_declare(TLIBC_ERROR);
+ErrorCodePage_declare(LIBC_ERRNO);
+
 typedef struct Result_ {
     Error* error;
     union {
@@ -46,9 +62,21 @@ typedef struct Result_ {
 ///USAGE: IGNORE_RESULT trySomething();
 #define IGNORE_RESULT Result_ __ignored_##__LINE__ ATTRIBUTE_UNUSED = 
 
-#define RESULT_ERROR(MSG, IS_MSG_ON_HEAP) (Result_){ .error = Error_create(MSG, IS_MSG_ON_HEAP, ErrorCallPos_here()) }
-#define RESULT_ERROR_FMT(FORMAT, ARGS...) RESULT_ERROR(sprintf_malloc(FORMAT ,##ARGS), true)
-#define RESULT_ERROR_ERRNO() RESULT_ERROR(strerror(errno), false)
+
+#define RESULT_ERROR_CODE(CODE_PAGE, CODE, MSG, IS_MSG_ON_HEAP) (Result_){ \
+    .error = Error_create(MSG, IS_MSG_ON_HEAP, ErrorCallPos_here(), \
+        ErrorCodePage_name(CODE_PAGE), CODE), \
+    .u = 0 \
+}
+#define RESULT_ERROR_CODE_FMT(CODE_PAGE, CODE, FORMAT, ARGS...) \
+    RESULT_ERROR_CODE(CODE_PAGE, CODE, sprintf_malloc(FORMAT ,##ARGS), true)
+#define RESULT_ERROR(MSG, IS_MSG_ON_HEAP) \
+    RESULT_ERROR_CODE(NONE, 0, MSG, IS_MSG_ON_HEAP);
+#define RESULT_ERROR_FMT(FORMAT, ARGS...) \
+    RESULT_ERROR_CODE_FMT(NONE, 0, FORMAT ,##ARGS)
+#define RESULT_ERROR_ERRNO() \
+    RESULT_ERROR_CODE(LIBC_ERRNO, errno, strerror(errno), false)
+
 #define RESULT_VOID (Result_){ .error = NULL, .u = 0 }
 #define RESULT_VALUE(FIELD, V) (Result_){ .error = NULL, .FIELD = V }
 
diff --git a/include/tlibc/tlibc.h b/include/tlibc/tlibc.h
new file mode 100644
index 0000000..b8cb3be
--- /dev/null
+++ b/include/tlibc/tlibc.h
@@ -0,0 +1,5 @@
+#include "tlibc/errors.h"
+
+/// call once at the start of main()
+Result(void) tlibc_init();
+void tlibc_deinit();
diff --git a/src/errors.c b/src/errors.c
index 673d247..84b7c77 100755
--- a/src/errors.c
+++ b/src/errors.c
@@ -3,10 +3,14 @@
 
 #define ERRMSG_LENGTH 1024
 
-Error* Error_create(const char* msg, bool is_msg_on_heap, ErrorCallPos p){
+Error* Error_create(const char* msg, bool is_msg_on_heap, ErrorCallPos p,
+    u16 error_code_page, u32 error_code)
+{
     Error* e = (Error*)malloc(sizeof(Error));
     e->msg = str_construct((char*)(void*)msg, strlen(msg), true);
     e->is_msg_on_heap = is_msg_on_heap;
+    e->error_code_page = error_code_page;
+    e->error_code = error_code;
     e->call_stack = List_alloc(ErrorCallPos, 16);
     Error_addCallPos(e, p);
     return e;
@@ -51,3 +55,12 @@ void Error_printAndExit(Error* e){
     Error_free(e);
     exit(111);
 }
+
+ErrorCodePage_define(TLIBC_ERROR);
+ErrorCodePage_define(LIBC_ERRNO);
+
+static u16 _error_code_page_last = 0;
+
+void _ErrorCodePage_register(u16* error_code_page_ptr){
+    *error_code_page_ptr = ++_error_code_page_last;
+}
diff --git a/src/tlibc.c b/src/tlibc.c
new file mode 100644
index 0000000..9befbd5
--- /dev/null
+++ b/src/tlibc.c
@@ -0,0 +1,14 @@
+#include "tlibc/tlibc.h"
+
+Result(void) tlibc_init(){
+    Deferral(8);
+
+    ErrorCodePage_register(TLIBC_ERROR);
+    ErrorCodePage_register(LIBC_ERRNO);
+
+    Return RESULT_VOID;
+}
+
+void tlibc_deinit(){
+
+}
\ No newline at end of file