Getting application ReadLine and Perl debugger ReadLine to cooperate

[Andrew DeFaria]

I have an example Perl script that uses Term::ReadLine::Gnu to provide
ReadLine support with command history:

#!/usr/local/bin/perl
use Term::ReadLine;
use Term::ReadLine::Gnu;

my $term = new Term::ReadLine "test";

while () {
$_ = $term->readline ("Command:");

last if !$_;

print "Read command: $_\n":
} # while

exit;

When run it runs fine, doesn't do much, but dutifully reads commands
and stores them in the history. IOW up arrow works to recall commands
and I can edit them. IOW Term::ReadLine::Gnu is installed properly and
functioning.

Now I wish to debug this script. So I do perl -d testReadLine.pl.
Initially the Perl debugger works. I can do commands like l for list
or s for step. However, as soon as I return from the new
Term::ReadLine the debugger is confused. No command does anything.

I fully suspect that the problem lies in the fact that both my Perl
script and the Perl debugger are fighting over STDIN/STDOUT and
confusing each other. The question is how to get them both to play
nice.

Suggestions? Workarounds? Solutions?

 

[Ben Morrow]

I have an example Perl script that uses Term::ReadLine::Gnu to provide
ReadLine support with command history:

#!/usr/local/bin/perl
use Term::ReadLine;
use Term::ReadLine::Gnu;

When run it runs fine, doesn't do much, but dutifully reads commands
and stores them in the history. IOW up arrow works to recall commands
and I can edit them. IOW Term::ReadLine::Gnu is installed properly and
functioning.

Now I wish to debug this script. So I do perl -d testReadLine.pl.
Initially the Perl debugger works. I can do commands like l for list
or s for step. However, as soon as I return from the new
Term::ReadLine the debugger is confused. No command does anything.

I fully suspect that the problem lies in the fact that both my Perl
script and the Perl debugger are fighting over STDIN/STDOUT and
confusing each other. The question is how to get them both to play
nice.

It may also be because the debugger is also using Term::Readline::Gnu. I
don't know if the underlying readline library can cope with two users at
once. You may want to try the debugger options TTY and ReadLine (see
perldoc perldebug).

Ben