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

fusl/src/temp/mkdtemp.c

Index: fusl/src/temp/mkdtemp.c
diff --git a/fusl/src/temp/mkdtemp.c b/fusl/src/temp/mkdtemp.c
new file mode 100644
index 0000000000000000000000000000000000000000..6c2c16ef2e8027e4f30a3d90be1c79f3502c73f9
--- /dev/null
+++ b/fusl/src/temp/mkdtemp.c
@@ -0,0 +1,25 @@
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/stat.h>
+
+char *__randname(char *);
+
+char *mkdtemp(char *template)
+{
+	size_t l = strlen(template);
+	int retries = 100;
+
+	if (l<6 || memcmp(template+l-6, "XXXXXX", 6)) {
+		errno = EINVAL;
+		return 0;
+	}
+
+	do {
+		__randname(template+l-6);
+		if (!mkdir(template, 0700)) return template;
+	} while (--retries && errno == EEXIST);
+
+	memcpy(template+l-6, "XXXXXX", 6);
+	return 0;
+}