diff --git a/vlib/os/os.v b/vlib/os/os.v
index 088aeb797d..47ea85b0c3 100644
--- a/vlib/os/os.v
+++ b/vlib/os/os.v
@@ -640,18 +640,6 @@ pub fn execute_or_exit(cmd string) Result {
 	return res
 }
 
-// is_atty returns 1 if the `fd` file descriptor is open and refers to a terminal
-pub fn is_atty(fd int) int {
-	$if windows {
-		mut mode := u32(0)
-		osfh := voidptr(C._get_osfhandle(fd))
-		C.GetConsoleMode(osfh, voidptr(&mode))
-		return int(mode)
-	} $else {
-		return C.isatty(fd)
-	}
-}
-
 pub fn glob(patterns ...string) ?[]string {
 	mut matches := []string{}
 	for pattern in patterns {
diff --git a/vlib/os/os_c.v b/vlib/os/os_c.v
index 8275a9f34a..2cc2bdb14f 100644
--- a/vlib/os/os_c.v
+++ b/vlib/os/os_c.v
@@ -977,3 +977,15 @@ pub fn execve(cmdpath string, args []string, envs []string) ? {
 		return error_with_code(posix_get_error_msg(C.errno), C.errno)
 	}
 }
+
+// is_atty returns 1 if the `fd` file descriptor is open and refers to a terminal
+pub fn is_atty(fd int) int {
+	$if windows {
+		mut mode := u32(0)
+		osfh := voidptr(C._get_osfhandle(fd))
+		C.GetConsoleMode(osfh, voidptr(&mode))
+		return int(mode)
+	} $else {
+		return C.isatty(fd)
+	}
+}