diff --git a/kernel/src/fs/stdio.rs b/kernel/src/fs/stdio.rs
index d2ceda2..2595926 100644
--- a/kernel/src/fs/stdio.rs
+++ b/kernel/src/fs/stdio.rs
@@ -57,7 +57,15 @@ macro_rules! impl_inode {
         fn move_(&self, _old_name: &str, _target: &Arc<INode>, _new_name: &str) -> Result<()> { Err(FsError::NotDir) }
         fn find(&self, _name: &str) -> Result<Arc<INode>> { Err(FsError::NotDir) }
         fn get_entry(&self, _id: usize) -> Result<String> { Err(FsError::NotDir) }
-        fn io_control(&self, _cmd: u32, _data: u32) -> Result<()> { Err(FsError::NotSupported) }
+        fn io_control(&self, cmd: u32, data: u32) -> Result<()> {
+            match cmd {
+                TIOCGWINSZ => {
+                    // pretend to be tty
+                    Ok(())
+                },
+                _ => Err(FsError::NotSupported)
+            }
+        }
         fn fs(&self) -> Arc<FileSystem> { unimplemented!() }
         fn as_any_ref(&self) -> &Any { self }
     };
diff --git a/kernel/src/syscall/mod.rs b/kernel/src/syscall/mod.rs
index ef12052..8deeaa2 100644
--- a/kernel/src/syscall/mod.rs
+++ b/kernel/src/syscall/mod.rs
@@ -194,12 +194,20 @@ pub fn syscall(id: usize, args: [usize; 6], tf: &mut TrapFrame) -> isize {
             warn!("sys_getegid is unimplemented");
             Ok(0)
         }
+        SYS_SETPGID => {
+            warn!("sys_setpgid is unimplemented");
+            Ok(0)
+        }
         // 110
         SYS_GETPPID => sys_getppid(),
         SYS_SETSID => {
             warn!("sys_setsid is unimplemented");
             Ok(0)
         }
+        SYS_GETPGID => {
+            warn!("sys_getpgid is unimplemented");
+            Ok(0)
+        }
         SYS_SIGALTSTACK => {
             warn!("sys_sigaltstack is unimplemented");
             Ok(0)
@@ -254,9 +262,17 @@ pub fn syscall(id: usize, args: [usize; 6], tf: &mut TrapFrame) -> isize {
         }
         SYS_NEWFSTATAT => sys_fstatat(args[0], args[1] as *const u8, args[2] as *mut Stat, args[3]),
         SYS_UNLINKAT => sys_unlinkat(args[0], args[1] as *const u8, args[2]),
-        SYS_READLINKAT => sys_readlinkat(args[0], args[1] as *const u8, args[2] as *mut u8, args[3]),
+        SYS_READLINKAT => {
+            sys_readlinkat(args[0], args[1] as *const u8, args[2] as *mut u8, args[3])
+        }
         SYS_RENAMEAT => sys_renameat(args[0], args[1] as *const u8, args[2], args[3] as *const u8),
-        SYS_LINKAT => sys_linkat(args[0], args[1] as *const u8, args[2], args[3] as *const u8, args[4]),
+        SYS_LINKAT => sys_linkat(
+            args[0],
+            args[1] as *const u8,
+            args[2],
+            args[3] as *const u8,
+            args[4],
+        ),
         SYS_SYMLINKAT => Err(SysError::EACCES),
         SYS_FACCESSAT => sys_faccessat(args[0], args[1] as *const u8, args[2], args[3]),
         // 280
diff --git a/kernel/src/util/mod.rs b/kernel/src/util/mod.rs
index ee7eb60..e1ecb67 100644
--- a/kernel/src/util/mod.rs
+++ b/kernel/src/util/mod.rs
@@ -83,4 +83,4 @@ pub fn write<T>(addr: usize, content: T) {
 pub fn read<T>(addr: usize) -> T {
     let cell = (addr) as *const T;
     unsafe { read_volatile(cell) }
-}
\ No newline at end of file
+}