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

fusl/src/misc/get_current_dir_name.c

Index: fusl/src/misc/get_current_dir_name.c
diff --git a/fusl/src/misc/get_current_dir_name.c b/fusl/src/misc/get_current_dir_name.c
new file mode 100644
index 0000000000000000000000000000000000000000..782cddcd826e76c21fe035da49e6f4d890b12c17
--- /dev/null
+++ b/fusl/src/misc/get_current_dir_name.c
@@ -0,0 +1,15 @@
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+char *get_current_dir_name(void) {
+	struct stat a, b;
+	char *res = getenv("PWD");
+	if (res && *res && !stat(res, &a) && !stat(".", &b)
+	    && (a.st_dev == b.st_dev) && (a.st_ino == b.st_ino))
+		return strdup(res);
+	return getcwd(0, 0);
+}