Scroll to navigation

MPI_UNPUBLISH_NAME(3) Open MPI MPI_UNPUBLISH_NAME(3) 

MPI_Unpublish_name - Unpublishes a service name


SYNTAX

C Syntax

#include <mpi.h>
int MPI_Unpublish_name(const char *service_name, MPI_Info info,


     const char *port_name)


Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_UNPUBLISH_NAME(SERVICE_NAME, INFO, PORT_NAME, IERROR)


     CHARACTER*(*)   SERVICE_NAME, PORT_NAME


     INTEGER         INFO, IERROR


Fortran 2008 Syntax

USE mpi_f08
MPI_Unpublish_name(service_name, info, port_name, ierror)


     CHARACTER(LEN=*), INTENT(IN) :: service_name, port_name


     TYPE(MPI_Info), INTENT(IN) :: info


     INTEGER, OPTIONAL, INTENT(OUT) :: ierror


INPUT PARAMETERS

  • service_name: A service name (string).
  • info: Options to the name service functions (handle).
  • port_name: A port name (string).

OUTPUT PARAMETER

•
ierror: Fortran only: Error status (integer).

DESCRIPTION

This routine removes the pair (service_name, port_name) so that applications may no longer retrieve port_name by calling MPI_Lookup_name <#mpi-lookup-name>. It is an error to unpublish a service_name that was not published via MPI_Publish_name <#mpi-publish-name>. Both the service_name and port_name arguments to MPI_Unpublish_name must be identical to the arguments to the previous call to MPI_Publish_name <#mpi-publish-name>.

INFO ARGUMENTS

The following keys for info are recognized:

Key                   Type      Description
---                   ----      -----------
range                 char *    Scope from which to remove the service


                                name.  See the NAME SCOPE section


                                below.


The range info key accepts one of two string values:

namespace) as the calling process.

session: Apply the operation across all processes in the same session.

If the info argument is MPI_INFO_NULL, or is a valid info object that does not contain a range key, session scope is used. Because MPI_Publish_name <#mpi-publish-name>, MPI_Lookup_name <#mpi-lookup-name>, and MPI_Unpublish_name all share this default, a name published with MPI_INFO_NULL is found by a lookup with MPI_INFO_NULL.

Any other value for range results in an error.

NAME SCOPE

Open MPI supports two name scopes, selected by the range info key: nspace and session.

nspace scope restricts the (service_name, port_name) pair to processes in the publisher’s own MPI job, i.e., processes sharing the publisher’s PMIx namespace.

session scope makes the pair visible to every process in the same PMIx session. This includes jobs started by separate mpirun invocations that share a persistent DVM or scheduler allocation, as well as jobs created via MPI_Comm_spawn <#mpi-comm-spawn>. session is the default scope.

The same scope must be used to publish, look up, and unpublish a given service name. MPI_Unpublish_name returns an error if the service name is not found in the indicated scope.

For a more detailed description of scoping rules, please see the MPI_Publish_name <#mpi-publish-name> man page.

ERRORS

Almost all MPI routines return an error value; C routines as the return result of the function and Fortran routines in the last argument.

Before the error value is returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. If no communication object is associated with the MPI call, then the call is considered attached to MPI_COMM_SELF and will call the associated MPI error handler. When MPI_COMM_SELF is not initialized (i.e., before MPI_Init <#mpi-init>/MPI_Init_thread <#mpi-init-thread>, after MPI_Finalize <#mpi-finalize>, or when using the Sessions Model exclusively) the error raises the initial error handler. The initial error handler can be changed by calling MPI_Comm_set_errhandler <#mpi-comm-set-errhandler> on MPI_COMM_SELF when using the World model, or the mpi_initial_errhandler CLI argument to mpiexec or info key to MPI_Comm_spawn <#mpi-comm-spawn>/MPI_Comm_spawn_multiple <#mpi-comm-spawn-multiple>. If no other appropriate error handler has been set, then the MPI_ERRORS_RETURN error handler is called for MPI I/O functions and the MPI_ERRORS_ABORT error handler is called for all other MPI functions.

Open MPI includes three predefined error handlers that can be used:

  • MPI_ERRORS_ARE_FATAL Causes the program to abort all connected MPI processes.
  • MPI_ERRORS_ABORT An error handler that can be invoked on a communicator, window, file, or session. When called on a communicator, it acts as if MPI_Abort <#mpi-abort> was called on that communicator. If called on a window or file, acts as if MPI_Abort <#mpi-abort> was called on a communicator containing the group of processes in the corresponding window or file. If called on a session, aborts only the local process.
  • MPI_ERRORS_RETURN Returns an error code to the application.

MPI applications can also implement their own error handlers by calling:

  • MPI_Comm_create_errhandler <#mpi-comm-create-errhandler> then MPI_Comm_set_errhandler <#mpi-comm-set-errhandler>
  • MPI_File_create_errhandler <#mpi-file-create-errhandler> then MPI_File_set_errhandler <#mpi-file-set-errhandler>
  • MPI_Session_create_errhandler <#mpi-session-create-errhandler> then MPI_Session_set_errhandler <#mpi-session-set-errhandler> or at MPI_Session_init <#mpi-session-init>
  • MPI_Win_create_errhandler <#mpi-win-create-errhandler> then MPI_Win_set_errhandler <#mpi-win-set-errhandler>

Note that MPI does not guarantee that an MPI program can continue past an error.

See the MPI man page <#open-mpi> for a full list of MPI error codes <#open-mpi-errors>.

See the Error Handling section of the MPI-3.1 standard for more information.

See also:

  • MPI_Publish_name <#mpi-publish-name>
  • MPI_Lookup_name <#mpi-lookup-name>
  • MPI_Open_port <#mpi-open-port>



Copyright

2003-2026, The Open MPI Community

September 21, 2026