How can I get the C function prototype from a SO(link by cc) on solaris using gdb?

[NewHaka@hotmail]

 hi,all
 
 (gdb 5.0 sparc solaris 8)
 
 I have a library link by sun cc,this library is complied and link
 with flag -g.
 
 I try to find out the prototype of functions in this library,gdb output:
(gdb) p GetDatVersion    
 $1 = {<text variable, no debug info>} 0xff273374 <GetDatVersion>
(gdb) p GetDatVersion
type = int ()
 
 Does the library must complied by gcc?
 
 
 Thanks.
 
 regards
 haka