Clarify a comment.

diff --git a/src/ttyname.c b/src/ttyname.c
index beb025431314062598eb17c5cf9942a0390e608c..02480ef0a2e5023d0b621c006f838b6a5f6333c7 100644 (file)
--- a/src/ttyname.c
+++ b/src/ttyname.c
@@ -247,9 +247,12 @@ sudo_ttyname_scan(const char *dir, dev_t rdev, bool builtin)
                continue;
        }
 # if defined(HAVE_STRUCT_DIRENT_D_TYPE) && defined(DTTOIF)
-       /* Use d_type to avoid a stat() if possible. */
-       /* Convert d_type to stat-style type bits but follow links. */
-       if (dp->d_type != DT_LNK && dp->d_type != DT_CHR && dp->d_type != DT_UNKNOWN)
+       /*
+        * Convert dp->d_type to sb.st_mode to avoid a stat(2) if possible.
+        * We can't use it for links (since we want to follow them) or
+        * char devs (since we need st_rdev to compare the device number).
+        */
+       if (dp->d_type != DT_UNKNOWN && dp->d_type != DT_LNK && dp->d_type != DT_CHR)
            sb.st_mode = DTTOIF(dp->d_type);
        else
 # endif