latex and perl mode

[Dietmar Kehr <dkehr@gnx.de>]

1. I can start a latex run with C-c C-b but 
this starts latex \\nonstopmode
How can I use latex without \\nonstopmode?

2. I'd like to use a similar feature in the perl-mode:
I would like to run the buffer with the perl programm, where 
the error messages are shown in seperate emacs buffer.
How is this possible? I didn't find it with C-h f perlmode.

Thanks.