Remark:

There is an optional arguments for the functions load, save, loadmesh, savemesh. This is the 2nd or 3rd argument of these functions. Here are the prototypes:

save(<filename>, <function name> 
    [,<variable counter: integer or converted to integer>])
load(<filename>, <function name> 
    [,<variable counter: integer or converted to integer>])
savemesh(<filename>[,<variable counter: 
                      integer or converted to integer>])
loadmesh(<filename>[,<variable counter: 
                      integer or converted to integer>])

As an example see nsstepad.pde which use this feature to save the mesh and the solution at each adaptation of the mesh. This special feature allows you to save or load a generic filename with a counter, the final filename is built like this '<generic filename>-<counter>'.