user: implement mlibc as the libc, finally.

It's finally done..

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

user/include/mlibc/abis/dripos/sigevent.h

@@ -0,0 +1,23 @@
+#ifndef _ABIBITS_SIGEVENT_H
+#define _ABIBITS_SIGEVENT_H
+
+#include <abi-bits/sigval.h>
+#include <abi-bits/pid_t.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct sigevent {
+	int sigev_notify;
+	int sigev_signo;
+	union sigval sigev_value;
+	void (*sigev_notify_function)(union sigval);
+	/* MISSING: sigev_notify_attributes */
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _ABIBITS_SIGEVENT_H */