long-options: add parse_gnu_standard_options_only Discussed in https://bugs.gnu.org/33468 . * lib/long-options.c (parse_long_options): Use EXIT_SUCCESS instead of 0. (parse_gnu_standard_options_only): Add function to process the GNU default options --help and --version and fail for any other unknown long or short option. See https://gnu.org/prep/standards/html_node/Command_002dLine-Interfaces.html . * lib/long-options.h (parse_gnu_standard_options_only): Declare it. * modules/long-options (depends-on): Add stdbool, exitfail. * top/maint.mk (sc_prohibit_long_options_without_use): Update syntax-check rule, add new function name.

--- a/top/maint.mk	Sun Feb 24 01:52:19 2019 +0100
+++ b/top/maint.mk	Thu Nov 29 09:06:26 2018 +0100
@@ -537,7 +537,7 @@
 
 # Don't include this header unless you use one of its functions.
 sc_prohibit_long_options_without_use:
-	@h='long-options.h' re='\<parse_long_options *\(' \
+	@h='long-options.h' re='\<parse_(long_options|gnu_standard_options_only) *\(' \
 	  $(_sc_header_without_use)
 
 # Don't include this header unless you use one of its functions.