[panda60]

Dear all,
I use functionObjedt like following:
functions
{
extraction
{
type surfaces;
functionObjectLibs ("libsampling.so");
enabled true;
outputControl timeStep;
outputInterval 5;
surfaceFormat foamFile;
interpolationScheme cellPointFace;
fields
(
U
T
);
surfaces
(
aplane
{
type plane;
basePoint (-0.4 0 0.5);
normalVector (1.0 0 0);
}
);
}
}

my purpose is to extract a plane data of internal domain in every time step. But the file directory is not what I want.
I copy src/sampling ,and modify a little ,create another called libmysampling.so.

but when using, it displays:

--> FOAM Warning :
From function dlLibraryTable:pen(const dictionary& dict, const word& libsEntry, const TablePtr tablePtr)
in file lnInclude/dlLibraryTableTemplates.C at line 68
library "libmysampling.so" did not introduce any new entries

It seems that my own libmysampling.so doesn't take effect.
Could any one tell me how to create functionObject type ?
Thanks.