18.2.411. MPI_T_cvar_read

MPI_T_cvar_read — Read the value of a control variable

18.2.411.1. SYNTAX

18.2.411.1.1. C Syntax

int MPI_T_cvar_read(MPI_T_cvar_handle handle, void* buf)

18.2.411.2. INPUT PARAMETERS

handle: Handle of the control variable to be read.
buf: Initial address of storage location for variable value.

18.2.411.3. DESCRIPTION

MPI_T_cvar_read reads the value of the control variable identified by the handle specified in handle and stores the value in the buffer pointed to by buf. The caller must ensure that the buffer pointed to by buf is large enough to hold the entire value of the control variable: for a string, count characters, where count is the value returned by MPI_T_cvar_handle_alloc.

If a string control variable’s value has grown longer than count - 1 characters since the handle was allocated, MPI_T_cvar_read stores only its first count - 1 characters, followed by a null character. Free the handle and allocate a new one to read the whole value.

18.2.411.4. ERRORS

MPI_T_cvar_read will fail if:

MPI_T_ERR_NOT_INITIALIZED: The MPI Tools interface not initialized
MPI_T_ERR_INVALID_HANDLE: The handle is invalid