MPI_Abort(3) LAM/MPI MPI_Abort(3)
MPI_Abort - Terminates MPI execution environment
int MPI_Abort(MPI_Comm comm, int errcode)
comm - communicator of tasks to abort
- error code to return to invoking environment
Makes a "best attempt" to terminate all MPI processes associated with the communicator
comm ; for non-IMPI jobs, this will terminate all processes. MPI_Abort will hang, how-
ever, if the LAM daemon on the node on which a rank was running has died. For example, if
a node gets powered off in the middle of an MPI run and MPI_Abort is invoked, it may hang
trying to contact the LAM daemon on the downed node.
In the case of an IMPI job, in addition to terminating all local IMPI procs, this function
will also send an abort message to the local IMPI host, which will, in turn send "closing"
messages to all the other IMPI hosts. Their behavior upon receipt of these "closing" mes-
sages is implementation dependant.
If the LAM IMPI host receives a premature "closing" message from a remote IMPI host, it
will attempt to continue processing. Any new messages to that host will likely hang, how-
'ERRCODE' IS SPLIT INTO THREE SECTIONS
lower 8 bits: error class
- . next 8 bits: function
upper 16 bits: error code
- If the error class is nonzero, the error code is the POSIX return value for the
program (i.e., exit(error_code) is eventually called to terminate the program). If
the error class is zero, errcode is returned as the POSIX return value for the pro-
This is mainly because MPI_Abort is used internally in LAM/MPI to abort MPI upon
error; LAM packs all three pieces of data into the POSIX return code. Users who
wish to return a specific value from the
PROGRAM SHOULD USE SOMETHING SIMILAR TO
return ((return_code << 16) + 1);
NOTES FOR FORTRAN
All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have an additional argu-
ment ierr at the end of the argument list. ierr is an integer and has the same meaning as
the return value of the routine in C. In Fortran, MPI routines are subroutines, and are
invoked with the call statement.
All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in Fortran.
For more information, please see the official MPI Forum web site, which contains the text
of both the MPI-1 and MPI-2 standards. These documents contain detailed information about
each MPI function (most of which is not duplicated in these man pages).
The LAM Team would like the thank the MPICH Team for the handy program to generate man
pages ("doctext" from ftp://ftp.mcs.anl.gov/pub/sowing/sowing.tar.gz ), the initial for-
matting, and some initial text for most of the MPI-1 man pages.
LAM/MPI 6.5.8 11/10/2002 MPI_Abort(3)