Readline catches SIGINT

[amagura]

Issue Description(s)

CSI responds to SIGINT differently after readline is loaded

When csi is started without an rc file (e.g. csi -n) it: responds to SIGINT immediately and prints a new prompt, however, when/after readline has been loaded, csi only responds to SIGINT after encountering a carriage return (\r): this behavior is awkward and differs from other major lisps implementations such as clisp and sbcl (both of which respond to SIGINT after a short pause without any further intervention from the user).

CSI reports an unknown variable named rl_catch_signals when loading readline.so

; loading /home/rr257875/usr/lib/chicken/8/readline.so ...
readline: rl_catch_signals: unknown variable name

After doing a small amount of research, I realized that the issue is caused by the following code in interface.c:

#endif
     rl_completion_entry_function = &gnu_readline_tab_complete;
     rl_variable_bind("rl_catch_signals", 0);
     rl_clear_signals();
     rl_set_signals();

In the code above, rl_variable_bind is being misused, it is not designed to set C variables, but readline variables such as you could set by calling set ... on the command-line.

The code should be something like this:

#endif
     rl_completion_entry_function = &gnu_readline_tab_complete;
     int rl_catch_signals = 0;
     rl_clear_signals();
     rl_set_signals();

This misuse does not seem to be present in trunk, but is present in the most recent release.

[amagura]

#8 would have resolved the issue with rl_catch_signals creating that warning in csi; however, I forgot to promote those changes into the wild.