MPI_TYPE_SET_NAME(3)

💅 MPI_TYPE_SET_NAME(3) — Open MPI, bestie edition ✨

Okay so this is the Open MPI manual page for MPI_TYPE_SET_NAME, and we're gonna get you fully caught up. No cap, it's a short one and it's lowkey iconic. 🎀

🌸 NAME

MPI_Type_set_name — gives a data type a name. Like, a cute little printable label. Yes, datatypes get names now. Slay. 💖

✨ SYNTAX

💻 C Syntax

#include <mpi.h>

int MPI_Type_set_name(MPI_Datatype type, const char *type_name)

🧚 Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_TYPE_SET_NAME(TYPE, TYPE_NAME, IERROR)
     INTEGER TYPE, IERROR
     CHARACTER*(*) TYPE_NAME

🦋 Fortran 2008 Syntax

USE mpi_f08
MPI_Type_set_name(datatype, type_name, ierror)
     TYPE(MPI_Datatype), INTENT(IN) :: datatype
     CHARACTER(LEN=*), INTENT(IN) :: type_name
     INTEGER, OPTIONAL, INTENT(OUT) :: ierror

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🌈 INPUT/OUTPUT PARAMETER

• type — the data type whose identifier is getting set (handle). It's giving main character energy, honestly. 👑

🍓 INPUT PARAMETER

• type_name — the character string that gets remembered as the name (string). That's it, that's the name. 💅

⭐ OUTPUT PARAMETER

• ierror — Fortran only: the error status (integer). 🫶

💜 DESCRIPTION

MPI_Type_set_name associates a printable identifier with an MPI data type.

Like. That's literally it. You hand it a datatype, you hand it a string, the string is now the printable identifier for that datatype. Cute, right? 🎀

🔥 ERRORS

Okay so this part is the long one, but stay with me bestie, it matters fr fr.

Almost all MPI routines return an error value. C routines give it back as the return result of the function, and Fortran routines put it in the last argument. 😌

Before the error value gets returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. And if there's, like, no communication object associated with the MPI call? Then the call is considered attached to MPI_COMM_SELF and it'll call the associated MPI error handler. 🫠

When MPI_COMM_SELF is not initialized (i.e., before MPI_Init/MPI_Init_thread, after MPI_Finalize, or when using the Sessions Model exclusively) the error raises the initial error handler. And you can change that initial error handler — by calling MPI_Comm_set_errhandler on MPI_COMM_SELF when using the World model, or with the mpi_initial_errhandler CLI argument to mpiexec, or the info key to MPI_Comm_spawn/MPI_Comm_spawn_multiple. The way there are so many doors into this. 🚪✨

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. Not me knowing exactly which one fires when. 💀

Open MPI includes three predefined error handlers that you can use:

• MPI_ERRORS_ARE_FATAL — causes the program to abort all connected MPI processes. Like, everyone. Gone. 😭
• 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 was called on that communicator. If called on a window or file, it acts as if MPI_Abort was called on a communicator containing the group of processes in the corresponding window or file. And if called on a session, it aborts only the local process. Context is everything, iykyk. 💅
• MPI_ERRORS_RETURN — returns an error code to the application. Chillest of the three, ngl. 🧊

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

• MPI_Comm_create_errhandler then MPI_Comm_set_errhandler
• MPI_File_create_errhandler then MPI_File_set_errhandler
• MPI_Session_create_errhandler then MPI_Session_set_errhandler or at MPI_Session_init
• MPI_Win_create_errhandler then MPI_Win_set_errhandler

⚠️ Note that MPI does not guarantee that an MPI program can continue past an error. Like, do not assume you get to keep vibing after a failure. 👀

See the MPI man page for a full list of MPI error codes. 📜

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

🦋 SEE ALSO

• MPI_Type_get_name

👑 COPYRIGHT

2003-2026, The Open MPI Community

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And that's the whole page, bestie — you ate that. 💖✨ This was the Open MPI MPI_TYPE_SET_NAME(3) page, dated Sep 11, 2026. Go forth and name your datatypes, periodt. 🎀🫶