Using a fresh (2 hours agoo) update of SVN branch v1.2, I've found that attribute MPI_APPNUM returns -1 (minus one) when an 'sequential' application is not launched through mpiexec.
Reading the MPI standard, I understand it should return a non-negative integer if defined, or it should not be defined at all. http://www.mpi-forum.org/docs/mpi-20-html/node113.htm#Node113 """ If an application was not spawned with MPI_COMM_SPAWN or MPI_COMM_SPAWN_MULTIPLE, and MPI_APPNUM doesn't make sense in the context of the implementation-specific startup mechanism, MPI_APPNUM is not set. """ I'm not sure if this is intended, but I report it anyway, sorry if this is issue was already reported. Regards, -- Lisandro Dalcín --------------- Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC) Instituto de Desarrollo Tecnológico para la Industria Química (INTEC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) PTLC - Güemes 3450, (3000) Santa Fe, Argentina Tel/Fax: +54-(0)342-451.1594
