8.1. Requirements

To meet the MPI profiling interface, an implementation of the MPI functions must

1. provide a mechanism through which all of the MPI defined functions may be accessed with a name shift. Thus all of the MPI functions (which normally start with the prefix `` MPI_'') should also be accessible with the prefix `` PMPI_''.


2. ensure that those MPI functions which are not replaced may still be linked into an executable image without causing name clashes.


3. document the implementation of different language bindings of the MPI interface if they are layered on top of each other, so that the profiler developer knows whether she must implement the profile interface for each binding, or can economise by implementing it only for the lowest level routines.


4. where the implementation of different language bindings is is done through a layered approach (e.g. the Fortran binding is a set of ``wrapper'' functions which call the C implementation), ensure that these wrapper functions are separable from the rest of the library.

This is necessary to allow a separate profiling library to be correctly implemented, since (at least with Unix linker semantics) the profiling library must contain these wrapper functions if it is to perform as expected. This requirement allows the person who builds the profiling library to extract these functions from the original MPI library and add them into the profiling library without bringing along any other unnecessary code.


5. provide a no-op routine MPI_PCONTROL in the MPI library.