Hi, all,
Could anyone tell me where can I find the library to change C++-comments
to C-comments.
Thanks.

Take a look at the SED tool (ie. stream editor). It's from the Unix
world and can do what you want. (Disclaimer: no, that's not standard
C, so you'd better not ask here on how to use it)

Stephan
(initiator of the campaign against grumpiness in c.l.c)