can someone tell me how to add functions to library of devc++? and how to add a new library?

I think menu Project --> Add To Project, then select the library you want to add. Could be wrong about that though.

maybe i`ve formulated the question wrong.
I`m talking about adding a new function i`ve created to the library , and creating a new library by myself and how to make it usable in dev cpp.
for example to add a new function i turbo c++ i use C:\>tlib math.lib + c:\fact.obj
and to delete a function use sign -. that`s what i`m talking about, if devcpp has this utility. but thx anyway.

thanks for the answer, it worked