:orphan: # PetscCommGetNewTag Gets a unique new tag from a PETSc communicator. All processors that share the communicator MUST call this routine EXACTLY the same number of times. This tag should only be used with the current objects communicator; do NOT use it with any other MPI communicator. ## Synopsis ``` #include "petscsys.h" PetscErrorCode PetscCommGetNewTag(MPI_Comm comm, PetscMPIInt *tag) ``` Collective ## Input Parameter - ***comm -*** the MPI communicator ## Output Parameter - ***tag -*** the new tag ## See Also `PetscObjectGetNewTag()`, `PetscCommDuplicate()` ## Level developer ## Location src/sys/objects/tagm.c --- [Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/sys/objects/tagm.c) [Index of all Sys routines](index.md) [Table of Contents for all manual pages](/manualpages/index.md) [Index of all manual pages](/manualpages/singleindex.md)