diff --git a/Libraries/LibCore/File.cpp b/Libraries/LibCore/File.cpp
index 27f36fdd401..a2f26cf7eb0 100644
--- a/Libraries/LibCore/File.cpp
+++ b/Libraries/LibCore/File.cpp
@@ -7,15 +7,11 @@
 
 #include <LibCore/File.h>
 #include <LibCore/System.h>
-#include <fcntl.h>
 
 #if !defined(AK_OS_WINDOWS)
 #    include <unistd.h>
 #else
-#    include <WinSock2.h>
-#    define STDIN_FILENO _fileno(stdin)
-#    define STDOUT_FILENO _fileno(stdout)
-#    define STDERR_FILENO _fileno(stderr)
+#    include <AK/Windows.h>
 #endif
 
 namespace Core {
diff --git a/Libraries/LibCore/System.h b/Libraries/LibCore/System.h
index 0a0b3eb122b..ed195985ba1 100644
--- a/Libraries/LibCore/System.h
+++ b/Libraries/LibCore/System.h
@@ -33,7 +33,11 @@
 #    include <utime.h>
 #else
 #    include "SocketAddressWindows.h"
+#    include <io.h>
 #    define O_CLOEXEC O_NOINHERIT
+#    define STDIN_FILENO _get_osfhandle(_fileno(stdin))
+#    define STDOUT_FILENO _get_osfhandle(_fileno(stdout))
+#    define STDERR_FILENO _get_osfhandle(_fileno(stderr))
 #    define S_ISDIR(mode) (((mode) & S_IFMT) == S_IFDIR)
 #    define S_ISREG(mode) (((mode) & S_IFMT) == S_IFREG)
 using sighandler_t = void (*)(int);
diff --git a/Libraries/LibCore/SystemWindows.cpp b/Libraries/LibCore/SystemWindows.cpp
index d5b021bf9cf..b6a0e7e03c2 100644
--- a/Libraries/LibCore/SystemWindows.cpp
+++ b/Libraries/LibCore/SystemWindows.cpp
@@ -276,4 +276,9 @@ ErrorOr<void> set_close_on_exec(int handle, bool enabled)
     return {};
 }
 
+ErrorOr<bool> isatty(int handle)
+{
+    return GetFileType(to_handle(handle)) == FILE_TYPE_CHAR;
+}
+
 }