diff --git a/kern/libkern/ctype.h b/kern/libkern/ctype.h
new file mode 100644
index 0000000..56ebbed
--- /dev/null
+++ b/kern/libkern/ctype.h
@@ -0,0 +1,8 @@
+#ifndef CTYPE_H
+#define CTYPE_H
+
+static inline int isprint(int c) {
+    return (unsigned)c - 0x20 < 0x5f;
+}
+
+#endif // CTYPE_H