diff --git a/.cargo/config b/.cargo/config.toml
similarity index 55%
rename from .cargo/config
rename to .cargo/config.toml
index b8e4014..f7cf539 100644
--- a/.cargo/config
+++ b/.cargo/config.toml
@@ -1,3 +1,6 @@
+[unstable]
+build-std = ["core", "compiler_builtins", "alloc"]
+
 [build]
 target = "i586-rust_dos.json"
 rustflags = ["-C", "link-arg=-Tlink.x"]
\ No newline at end of file
diff --git a/Cargo.toml b/Cargo.toml
index d4f95c8..da37c76 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,3 +10,4 @@ edition = "2018"
 opt-level = "z"
 
 [dependencies]
+rlibc = "1.0.0"
diff --git a/README.md b/README.md
index 69b5099..3e436f1 100644
--- a/README.md
+++ b/README.md
@@ -4,10 +4,9 @@ It is possible to create a DOS executable or 1st stage bootloader with Rust.
 This is a quick demo of creating COM executable for DOS.
 
 ## Building
-You need a nightly Rust compiler and binutils. First you need to install the [cargo-xbuild](https://github.com/rust-osdev/cargo-xbuild) and [cargo-binutils](https://github.com/rust-embedded/cargo-binutils):
+You need a binutils and llvm-tools-preview.
 
 ```shell
-cargo install cargo-xbuild 
 cargo install cargo-binutils
 rustup component add llvm-tools-preview
 ```
@@ -15,26 +14,31 @@ rustup component add llvm-tools-preview
 Then you can build the project by running:
 
 ```shell
-cargo xbuild --release
+cargo build --release
 ```
 
 To create a COM executable for DOS, run:
 
 ```shell
-cargo objcopy -- -I elf32-i386 -O binary --binary-architecture=i386:x86 \
-  target/i586-rust_dos/release/rust_dos target/i586-rust_dos/release/rust_dos.com
+cargo objcopy --release -O binary --binary-architecture=i386:x86 rust_dos.com
 ```
 
 ## Running
-You can copy `rust_dos.com` to your DOS image.  
+You can copy `rust_dos.com` to your DOS image.
 
-examples on macOS:
+examples on Linux
 
 ```shell
-$ hdiutil attach path/to/freedos.img 
-/dev/disk2          	FDisk_partition_scheme         	
-/dev/disk2s1        	DOS_FAT_16                     	/Volumes/FREEDOS2016
-$ cp target/i586-rust_dos/release/rust_dos.com /Volumes/FREEDOS2016/
+$ sudo partx -av freedos.img
+partition: none, disk: freedos.img, lower: 0, upper: 0
+Trying to use '/dev/loop1' for the loop device
+/dev/loop1: partition table type 'dos' detected
+range recount: max partno=1, lower=0, upper=0
+/dev/loop1: partition #1 added
+$ sudo mount /dev/loop1p1 /mnt
+$ sudo cp rust_dos.com /mnt/
+$ sudo umount /mnt
+$ sudo partx -dv /dev/loop1
 ```
 
 Then, you can test it using QEMU:
@@ -43,13 +47,13 @@ Then, you can test it using QEMU:
 qemu-system-i386 freedos.img -boot c
 ```
 
-You can use the `println!` macro.  
+You can use the `println!` macro. 
 Below is an example of HelloWorld:
 
-![sample](https://github.com/ellbrid/rust_dos/blob/images/rust_dos_hello.png)
+![sample](https://github.com/o8vm/rust_dos/blob/images/rust_dos_hello.png)
 
 ### Others
 dpkey module steals key input processing from DOS and converts scan code to ascii code.  
 about scan code: see [PS/2 Keyboard - OSDev Wiki](https://wiki.osdev.org/PS/2_Keyboard).
 
-![sample2](https://github.com/ellbrid/rust_dos/blob/images/dpkey.gif)
+![sample2](https://github.com/o8vm/rust_dos/blob/images/dpkey.gif)
diff --git a/i586-rust_dos.json b/i586-rust_dos.json
index 0b37e35..f391cd1 100644
--- a/i586-rust_dos.json
+++ b/i586-rust_dos.json
@@ -22,4 +22,4 @@
     "vendor": "unknown",
     "panic-strategy": "abort",
     "disable-redzone": true
-}
\ No newline at end of file
+}
diff --git a/link.x b/link.x
index 847de1e..155b791 100644
--- a/link.x
+++ b/link.x
@@ -10,4 +10,5 @@ SECTIONS {
   .data   : { *(.data) }   > dos
   .bss    : { *(.bss) }    > dos
   .stack  : { *(.stack) }  > dos
-}
\ No newline at end of file
+  /DISCARD/ : { *(.eh_frame*) }
+}
diff --git a/src/dos.rs b/src/dos.rs
index 51f304b..41e8fee 100644
--- a/src/dos.rs
+++ b/src/dos.rs
@@ -6,11 +6,8 @@ pub mod kbc;
 
 pub fn exit(rt: u8) -> ! {
     unsafe {
-        asm!("mov $$0x4C, %ah
-              int $$0x21"
-              :
-              : "{al}"(rt)
-              : "eax");
+        asm!("mov ah, 0x4C",
+             "int 0x21", in("al") rt);
     }
     loop {}
-}
\ No newline at end of file
+}
diff --git a/src/dos/console.rs b/src/dos/console.rs
index b681db4..4125721 100644
--- a/src/dos/console.rs
+++ b/src/dos/console.rs
@@ -36,10 +36,6 @@ impl Write for DosWriter {
 
 fn printc(ch: u8) {
     unsafe {
-        asm!("mov $$0x2, %ah
-              int $$0x21"
-              :
-              : "{dl}"(ch)
-              : "eax", "edx");
+        asm!("int 0x21", in("ah") 0x02_u8, in("dl") ch)
     }
-}
\ No newline at end of file
+}
diff --git a/src/dos/io.rs b/src/dos/io.rs
index 9450bee..c27bc51 100644
--- a/src/dos/io.rs
+++ b/src/dos/io.rs
@@ -1,11 +1,7 @@
 pub fn inb(port: usize) -> u8 {
     let mut ret: u8;
     unsafe {
-        asm!("xorl %eax, %eax
-              inb  %dx,  %al"
-             : "={al}"(ret)
-             : "{dx}"(port)
-            );
+        asm!("in al, dx", out("al") ret, in("dx") port);
     }
     ret
 }
@@ -13,29 +9,19 @@ pub fn inb(port: usize) -> u8 {
 pub fn inw(port: usize) -> u16 {
     let mut ret: u16;
     unsafe {
-        asm!("xorl %eax, %eax
-              inw  %dx,  %ax"
-             : "={ax}"(ret)
-             : "{dx}"(port)
-            );
+        asm!("in ax, dx", out("ax") ret, in("dx") port)
     }
     ret
 }
 
 pub fn outb(data: u8, port: usize) {
     unsafe {
-        asm!("outb %al, %dx"
-             :
-             : "{al}"(data), "{dx}"(port)
-            );
+        asm!("out dx, al", in("dx") port, in("al") data);
     }
 }
 
 pub fn outw(data: u16, port: usize) {
     unsafe {
-        asm!("outw %ax, %dx"
-             :
-             : "{ax}"(data), "{dx}"(port)
-            );
+        asm!("out dx, ax", in("dx") port, in("ax") data);
     }
-}
\ No newline at end of file
+}
diff --git a/src/main.rs b/src/main.rs
index b80a364..900c225 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -9,4 +9,4 @@ fn main() {
     println!("Hello, World!");
     // println!("Hit any Key, please.");
     // dpkey::keymap();
-}
\ No newline at end of file
+}