I've put some php code inside a sidebar-01.php

i love during my template file to obtain that code

How can u do this ? (i do not things to alter the code of Wordpress for upgrading purpose)

i've try include('sidebar-01.php) - it aren't effective

i love to possess a function like : get_header() for my file, something similar to : get_file('sidebar-01')

is it feasible ?

Try the get_sidebar() function defined in wp-includes/general-template.php

Visit the 'Theme Editor', search for sidebar.php. Edit it and put this code there:

include('sidebar-01.php');

Also, make sure to place your sidebar-01.php in same folder because the other theme .php files (essentially your theme folder).