MPI_TYPE_SET_NAME(3)

💖 MPI_TYPE_SET_NAME 💖

okay bestie, gather round, because we're talking about MPI_TYPE_SET_NAME(3) from the Open MPI manual — yes that's the manual name, that's the vibe, that's the whole energy. it's a Fortran-callable MPI routine and it's honestly so simple you're gonna be obsessed. 💅

---

✨ NAME ✨

MPI_Type_set_name — sets the name of a data type.

like. that's it. that's the whole job. give your data type a little name tag so it can feel seen. 🎀

---

🌸 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

---

🫶 INPUT/OUTPUT PARAMETER 🫶

• type — the data type whose identifier is getting set, i.e. the handle. it's the glow-up recipient. handle energy ✨

---

🌈 INPUT PARAMETER 🌈

• type_name — the character string that gets remembered as the name. this is the little name tag, the group-chat nickname, the "hey bestie" of strings. string 💖

---

🦋 OUTPUT PARAMETER 🦋

• ierror — Fortran only: error status (integer). she reports back, always. 😭

---

👑 DESCRIPTION 👑

MPI_Type_set_name associates a printable identifier with an MPI data type.

that's the whole plot. you hand her a data type, you hand her a string, and now that data type is named. iconic. and fr fr, that name is printable, so it's meant to be looked at, not just vibing in the void. 🌟

---

💀 ERRORS 💀

okay this is the long section, but listen — don't skip it, this is where the actual lore lives. almost all MPI routines return an error value; C routines hand it back as the return result of the function, and Fortran routines put it in the last argument. periodt.

before that error value comes back to you, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. and if there's 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 instead. the way that works is so specific, i love it. 🫶

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 guess what — you can change the initial error handler! either by calling MPI_Comm_set_errhandler on MPI_COMM_SELF when you're 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. and 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. slay, very demure, very consistent. 💅

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

• MPI_ERRORS_ARE_FATAL — causes the program to abort all connected MPI processes. dramatic? yes. effective? also yes. 💀
• 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. if called on a session, it aborts only the local process. different vibes per object, lowkey iconic
• MPI_ERRORS_RETURN — returns an error code to the application. the chill one. the one that just hands you the receipt. 🧾✨

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. i'm being so serious right now. no cap. 😭

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 — the other half of the duo, the reading to this writing. iykyk 💜

---

🎀 COPYRIGHT 🎀

Copyright 2003-2026, The Open MPI Community

---

okay that's the whole page, you ate that, no crumbs left. 💅✨ this was MPI_TYPE_SET_NAME(3), straight out of the Open MPI fam, and the date on this little masterpiece is Sep 10, 2026 — remember it, because that's when this slay was documented. bye bestie, go name a data type, you've earned it 🦋💖🎀