doc: id: be direct about valid options with -nr

* src/id.c (usage): State what options are valid with -nr,
rather than just stating the default format is invalid.
Fixes https://bugs.gnu.org/77163

diff --git a/src/id.c b/src/id.c
index 2f1df41f0d09fd9aae3f8bdc2ad189f39e4493e0..d69e6e323606e2e2ed839470d4ff6377645e8fd2 100644 (file)
--- a/src/id.c
+++ b/src/id.c
@@ -198,7 +198,7 @@ main (int argc, char **argv)
 
   if (default_format && (use_real || use_name))
     error (EXIT_FAILURE, 0,
-           _("cannot print only names or real IDs in default format"));
+           _("printing only names or real IDs requires -u, -g, or -G"));
 
   if (default_format && opt_zero)
     error (EXIT_FAILURE, 0,