_foo_bar.c _foo_bar_baz.c _bar.c and _bif.c hello_bar.c and there_bif.c var this__is_a_variable__ = ""; __this is not__ ---

<lib>_foo_bar.c
<lib>_foo_bar_baz.c
<prefix>_bar.c and <prefix>_bif.c
hello_bar.c and there_bif.c

var this__is_a_variable__ = "";

this is not