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.