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

fusl/src/misc/getdomainname.c

Index: fusl/src/misc/getdomainname.c
diff --git a/fusl/src/misc/getdomainname.c b/fusl/src/misc/getdomainname.c
new file mode 100644
index 0000000000000000000000000000000000000000..59df566d9465625f28f47dcdaf979cf44c5681a7
--- /dev/null
+++ b/fusl/src/misc/getdomainname.c
@@ -0,0 +1,17 @@
+#define _GNU_SOURCE
+#include <unistd.h>
+#include <sys/utsname.h>
+#include <string.h>
+#include <errno.h>
+
+int getdomainname(char *name, size_t len)
+{
+	struct utsname temp;
+	uname(&temp);
+	if (!len || strlen(temp.domainname) >= len) {
+		errno = EINVAL;
+		return -1;
+	}
+	strcpy(name, temp.domainname);
+	return 0;
+}