Add a "fork" of musl as //fusl.

fusl/src/ipc/msgsnd.c

Index: fusl/src/ipc/msgsnd.c
diff --git a/fusl/src/ipc/msgsnd.c b/fusl/src/ipc/msgsnd.c
new file mode 100644
index 0000000000000000000000000000000000000000..23f4a4cbf58cc204343eb8fedb34f83bc2bd4de0
--- /dev/null
+++ b/fusl/src/ipc/msgsnd.c
@@ -0,0 +1,13 @@
+#include <sys/msg.h>
+#include "syscall.h"
+#include "ipc.h"
+#include "libc.h"
+
+int msgsnd(int q, const void *m, size_t len, int flag)
+{
+#ifdef SYS_msgsnd
+	return syscall_cp(SYS_msgsnd, q, m, len, flag);
+#else
+	return syscall_cp(SYS_ipc, IPCOP_msgsnd, q, len, flag, m);
+#endif
+}