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

fusl/src/errno/strerror.c

Index: fusl/src/errno/strerror.c
diff --git a/fusl/src/errno/strerror.c b/fusl/src/errno/strerror.c
new file mode 100644
index 0000000000000000000000000000000000000000..24c94d3742d4ed013dea3ef5625bfc03fd189a05
--- /dev/null
+++ b/fusl/src/errno/strerror.c
@@ -0,0 +1,37 @@
+#include <errno.h>
+#include <string.h>
+#include "locale_impl.h"
+#include "libc.h"
+
+#define E(a,b) ((unsigned char)a),
+static const unsigned char errid[] = {
+#include "__strerror.h"
+};
+
+#undef E
+#define E(a,b) b "\0"
+static const char errmsg[] =
+#include "__strerror.h"
+;
+
+char *__strerror_l(int e, locale_t loc)
+{
+	const char *s;
+	int i;
+	/* mips has one error code outside of the 8-bit range due to a
+	 * historical typo, so we just remap it. */
+	if (EDQUOT==1133) {
+		if (e==109) e=-1;
+		else if (e==EDQUOT) e=109;
+	}
+	for (i=0; errid[i] && errid[i] != e; i++);
+	for (s=errmsg; i; s++, i--) for (; *s; s++);
+	return (char *)LCTRANS(s, LC_MESSAGES, loc);
+}
+
+char *strerror(int e)
+{
+	return __strerror_l(e, CURRENT_LOCALE);
+}
+
+weak_alias(__strerror_l, strerror_l);