enable vi command line editing from .perldb rc afterinit in perl debugger

Question

Whenever I start the perl debugger from a script with a -d option, the session starts with emacs command line editing. I then type ESC ctrl J to enable vi editing. I want to enable vi from the get-go.

I tried using the following .perldb:

&parse_options("HistFile=.perlDebugHist");
 sub afterinit { push @DB::typeahead, ("o inhibit_exit", chr(27).chr(10)) }

but when the session starts, it says

auto(-2)  DB<62> o inhibit_exit
        inhibit_exit = '1'
auto(-1)  DB<63> 

Unrecognized character \x1B; marked by <-- HERE after :db_stop;
<-- HERE near column 96 at (eval 9)[/usr/share/perl/5.22/perl5db.pl:737] line 2.
 at (eval 9)[/usr/share/perl/5.22/perl5db.pl:737] line 2.
    eval 'no strict; ($@, $!, $^E, $,, $/, $\\, $^W) = @DB::saved;package main; $^D = $^D | $DB::db_stop;
;
' called at /usr/share/perl/5.22/perl5db.pl line 737
    DB::eval called at /usr/share/perl/5.22/perl5db.pl line 3110
    DB::DB called at ~/bin/debug.pl line 61

Answer 1

Here is a possible workaround that assumes you use the gnu readline library:

Create a file called perldb_inputrc in the current directory with content:

set editing-mode vi

Then change the afterinit() sub to:

sub afterinit {
  if (!$DB::term) {
    DB::setterm();
  }
  $DB::term->read_init_file('perldb_inputrc');
  push @DB::typeahead, "o inhibit_exit";
}

See perldoc perl5db for more information.

Update:

A simpler approach is to the readline init file. You can use a global file ~/.inputrc or a use a local one for the current debugging session only by setting the environment variable INPUTRC. For example, using the above perldb_inputrc file as an example, you could use (in your .perldb init file):

sub afterinit { push @DB::typeahead, "o inhibit_exit" }

and then run the Perl script like this:

INPUTRC=./perldb_inputrc perl -d myscript.pl