diff --git a/src/header/sys_ioctl/redox/mod.rs b/src/header/sys_ioctl/redox/mod.rs
index d0965ec8c1..74fb808bb0 100644
--- a/src/header/sys_ioctl/redox/mod.rs
+++ b/src/header/sys_ioctl/redox/mod.rs
@@ -38,6 +38,20 @@ pub const FIONREAD: c_ulong = 0x541B;
 
 pub const FIONBIO: c_ulong = 0x5421;
 
+pub const TIOCM_LE: c_ulong = 0x001;
+pub const TIOCM_DTR: c_ulong = 0x002;
+pub const TIOCM_RTS: c_ulong = 0x004;
+pub const TIOCM_ST: c_ulong = 0x008;
+pub const TIOCM_SR: c_ulong = 0x010;
+pub const TIOCM_CTS: c_ulong = 0x020;
+pub const TIOCM_CAR: c_ulong = 0x040;
+pub const TIOCM_CD: c_ulong = TIOCM_CAR;
+pub const TIOCM_RNG: c_ulong = 0x080;
+pub const TIOCM_RI: c_ulong = TIOCM_RNG;
+pub const TIOCM_DSR: c_ulong = 0x100;
+pub const TIOCMGET: c_ulong = 0x5415;
+pub const TIOCMSET: c_ulong = 0x5418;
+
 pub const TIOCSPTLCK: c_ulong = 0x4004_5431;
 pub const TIOCGPTLCK: c_ulong = 0x8004_5439;
 
diff --git a/src/header/termios/redox.rs b/src/header/termios/redox.rs
index 526e59aa51..a2951403f4 100644
--- a/src/header/termios/redox.rs
+++ b/src/header/termios/redox.rs
@@ -92,6 +92,7 @@ pub const PARODD: usize = 0o020_000;
 pub const HUPCL: usize = 0o040_000;
 
 pub const CLOCAL: usize = 0o0100000;
+pub const CRTSCTS: usize = 0o20_000_000_000;
 /* } c_clfag */
 
 /* c_lflag { */