Add build system scaffolding and libc headers

1 files changed, 12 insertions, 0 deletions

diff --git a/lib/libc/ctype/isalnum.c b/lib/libc/ctype/isalnum.c
new file mode 100644
index 00000000..04e94fc6
--- /dev/null
+++ b/lib/libc/ctype/isalnum.c
@@ -0,0 +1,12 @@
+#include <libc.h>
+#include <ctype.h>
+
+int isalnum(int c)
+{
+	return isalpha(c) || isdigit(c);
+}
+
+weak int isalnum_l(int c, locale_t unused locale)
+{
+	return isalnum(c);
+}