+#ifdef SUPPORT_PREALLOCATION
+#ifdef PREALLOCATE_NEEDS_TRUNCATE
+ OFF_T preallocated_len = 0;
+#endif
+
+ if (preallocate_files && fd != -1 && total_size > 0) {
+ /* Try to preallocate enough space for file's eventual length. Can
+ * reduce fragmentation on filesystems like ext4, xfs, and NTFS. */
+ if (do_fallocate(fd, 0, total_size) == 0) {
+#ifdef PREALLOCATE_NEEDS_TRUNCATE
+ preallocated_len = total_size;
+#endif
+ } else
+ rsyserr(FWARNING, errno, "do_fallocate %s", full_fname(fname));
+ }
+#endif