Hi, See below for the outdated document. Since -B is discouraged, it may be better to be documented. Thanks.
$ info m4 | grep 'GNU M4 (version' This manual (31 December 2016) is for GNU M4 (version 1.4.18), a package $ info m4 | grep prepend-include -A 3 If the '--prepend-include' or '-B' command-line option was provided (*note Invoking m4: Preprocessor features.), those directories are searched first, in reverse order that those options were listed on the command line. Then 'm4' looks in the current working directory. Next $ m4 --version m4 (GNU M4) 1.4.18 Copyright (C) 2016 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Written by Rene' Seindal. $ m4 -B . < /dev/null m4: warning: `m4 -B' may be removed in a future release -- Regards, Peng
