MPI\_T\_PVAR\_RESET(3) Open MPI MPI\_T\_PVAR\_RESET(3)

MPI\_T\_pvar\_reset — Reset the value of a performance variable

# [SYNTAX](#SYNTAX)

## [C Syntax](#C_Syntax)

```
#include <mpi.h>
int MPI_T_pvar_reset(MPI_T_pvar_session session, MPI_T_pvar_handle handle)
```

# [INPUT PARAMETERS](#INPUT_PARAMETERS)

- **session**: Performance experiment session.
- **handle**: Performance variable handle or MPI\_T\_PVAR\_ALL\_HANDLES.

# [DESCRIPTION](#DESCRIPTION)

MPI\_T\_pvar\_reset sets the performance variable specified by the handle in *handle* to its initial value. The special value MPI\_T\_PVAR\_ALL\_HANDLES can be passed in *handle* to reset all read-write handles in the session specified in *session*.

# [ERRORS](#ERRORS)

MPI\_T\_pvar\_reset will fail if:

- **MPI\_T\_ERR\_NOT\_INITIALIZED**: The MPI Tools interface not initialized
- **MPI\_T\_ERR\_INVALID\_HANDLE**: The handle is invalid
- **MPI\_T\_ERR\_INVALID\_SESSION**: Session argument is not a valid session
- **MPI\_T\_ERR\_PVAR\_NO\_WRITE**: Variable cannot be reset

**See also:**

- MPI\_T\_pvar\_handle\_alloc &lt;#mpi-t-pvar-handle-alloc&gt;
- MPI\_T\_pvar\_get\_info &lt;#mpi-t-pvar-get-info&gt;
- MPI\_T\_pvar\_session\_create &lt;#mpi-t-pvar-session-create&gt;
- MPI\_T\_pvar\_write &lt;#mpi-t-pvar-write&gt;

# [Copyright](#Copyright)

2003-2026, The Open MPI Community

November 1, 2026

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Document: MPI_T_pvar_reset(3) from openmpi-cuda-12.9 5.0.11-r1 (Chainguard OS)
Source: https://github.com/open-mpi/ompi