I have created 2 dlls : Dll_1 and Dll_2 Open a file with fopen(...) function in Dll_1 and return file stream structure pointer(FILE*) But the "unhandled exception..." happened when i try to read datas with fread(...) function in Dll_2 ,the file stream pointer is get from Dll_1,and it''s valid before fread() function when i Trace it. but if use Dll_1 in a client execute file ,nothing error getted. Does dlls read file stream data from opened in another Dll is invalid useage? need someone dll experts help me... thanks!!! & Very thanks for reading my ugly englis...

quote:...It''s valid before fread() function when i Trace it

The pointer points to something, yes, but what it points to means nothing in the context of the other DLL.
AFAIK you can''t transfer FILE*s out of a DLL and expect them to work. I''m not sure (untested), but Win32 style files (from CreateFile(), OpenFile(), ReadFile(), ...) might work ok.

HTH