Hi Bruno, I'm not sure handle_color_option works as expected. I always (independently of the argument of the option, and independently of whether the output is a tty) get colored output on Bison (https://github.com/akimd/bison/pull/5), but also in the two examples of libtextstyle.
As a workaround, currently I'm using this: void err_begin_use_class (const char *s) { #if HAVE_LIBTEXTSTYLE if (color_mode != color_no) styled_ostream_begin_use_class (errstream, s); #else (void) s; #endif } I might be doing something wrong, but I think I followed properly the documentation. Cheers!