From: Andrea Bolognani Date: Tue, 9 Apr 2019 13:56:54 +0000 (+0200) Subject: m4: readline: Comment rl_completion_quote_character() check X-Git-Tag: v5.3.0-rc1~148 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a9443bc9a9ef451b46306e66ed3b706756fc1414;p=thirdparty%2Flibvirt.git m4: readline: Comment rl_completion_quote_character() check The check was added in 74416b1d4849 without offering any explanation outside of the commit message. Introduce a comment to make digging through the git history unnecessary. Signed-off-by: Andrea Bolognani Reviewed-by: Daniel P. Berrangé --- diff --git a/m4/virt-readline.m4 b/m4/virt-readline.m4 index 4823a27788..649a52edfa 100644 --- a/m4/virt-readline.m4 +++ b/m4/virt-readline.m4 @@ -37,6 +37,12 @@ AC_DEFUN([LIBVIRT_CHECK_READLINE],[ LIBS="$lv_saved_libs $extra_LIBS" fi + # This function is present in all reasonable (5.0+) readline versions; + # however, the macOS base system contains a library called libedit which + # takes over the readline name despite lacking many of its features. We + # want to make sure we only enable readline support when linking against + # the actual readline library, and the availability of this specific + # functions is as good a witness for that fact as any. AC_CHECK_DECLS([rl_completion_quote_character], [], [], [[#include