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diff --git a/lib/makepath.c b/lib/makepath.c
index e6e65f632a1afbaf66c965a238de389d1e32ffb7..17844318a51e653d19e8626c7ebc0be8ab8fa6fc 100644 (file)
--- a/lib/makepath.c
+++ b/lib/makepath.c
@@ -210,6 +210,9 @@ make_path (argpath, mode, parent_mode, owner, group, preserve_existing,
              saved_cwd = !save_cwd (&cwd);
            }
 
+         /* If save_cwd could not record the current directory, then don't
+            do the chdir optimization and resort to using full pathnames.  */
+
          if (!saved_cwd)
            basename_dir = dirpath;
 
@@ -258,6 +261,10 @@ make_path (argpath, mode, parent_mode, owner, group, preserve_existing,
              leading_dirs = new;
            }
 
+         /* If we were able to save the initial working directory,
+            then we can use chdir to change into each directory before
+            creating an entry in that directory.  This avoids making
+            stat and mkdir process O(n^2) file name components.  */
          if (saved_cwd && chdir (basename_dir) < 0)
            {
              error (0, errno, "cannot chdir to directory, %s", dirpath);