diff --git a/headers/posix/termios.h b/headers/posix/termios.h
index e8ec24428a..0be1e3cc1b 100644
--- a/headers/posix/termios.h
+++ b/headers/posix/termios.h
@@ -235,6 +235,7 @@ extern int		tcdrain(int fd);
 extern int		tcflow(int fd, int action);
 extern int		tcflush(int fd, int queueSelector);
 extern pid_t	tcgetsid(int fd);
+extern int		tcsetsid(int fd, pid_t pid);
 
 #ifdef __cplusplus
 }
diff --git a/src/system/libroot/posix/termios.c b/src/system/libroot/posix/termios.c
index 18b9c96c2f..5f559bedc9 100644
--- a/src/system/libroot/posix/termios.c
+++ b/src/system/libroot/posix/termios.c
@@ -180,3 +180,15 @@ tcgetsid(int fd)
 	return -1;
 }
 
+
+int
+tcsetsid(int fd, pid_t pid)
+{
+	if (pid != getsid(0)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	return ioctl(fd, TIOCSCTTY, NULL);
+}
+