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

fusl/src/stdio/tempnam.c

Index: fusl/src/stdio/tempnam.c
diff --git a/fusl/src/stdio/tempnam.c b/fusl/src/stdio/tempnam.c
new file mode 100644
index 0000000000000000000000000000000000000000..5a5597527c0851d5d2c45fff1c6f1e2459e81375
--- /dev/null
+++ b/fusl/src/stdio/tempnam.c
@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <limits.h>
+#include <string.h>
+#include "syscall.h"
+
+#define MAXTRIES 100
+
+char *__randname(char *);
+
+char *tempnam(const char *dir, const char *pfx)
+{
+	char s[PATH_MAX];
+	size_t l, dl, pl;
+	int try;
+	int r;
+
+	if (!dir) dir = P_tmpdir;
+	if (!pfx) pfx = "temp";
+
+	dl = strlen(dir);
+	pl = strlen(pfx);
+	l = dl + 1 + pl + 1 + 6;
+
+	if (l >= PATH_MAX) {
+		errno = ENAMETOOLONG;
+		return 0;
+	}
+
+	memcpy(s, dir, dl);
+	s[dl] = '/';
+	memcpy(s+dl+1, pfx, pl);
+	s[dl+1+pl] = '_';
+	s[l] = 0;
+
+	for (try=0; try<MAXTRIES; try++) {
+		__randname(s+l-6);
+#ifdef SYS_lstat
+		r = __syscall(SYS_lstat, s, &(struct stat){0});
+#else
+		r = __syscall(SYS_fstatat, AT_FDCWD, s,
+			&(struct stat){0}, AT_SYMLINK_NOFOLLOW);
+#endif
+		if (r == -ENOENT) return strdup(s);
+	}
+	return 0;
+}