MPI_Info(3)MPI_Info(3)NAME
MPI_Info - Allocates memory for MPI arguments
SYNOPSIS
C:
#include "mpi.h"
MPI_Fint MPI_Info_c2f(MPI_Info file)
MPI_Info_create(info)
int MPI_Info_create(MPI_Info *info)
MPI_Info_delete(info, key)
int MPI_Info_delete(MPI_Info info, char *key)
MPI_Info_dup(info, newinfo)
int MPI_Info_dup(MPI_Info info, MPI_Info *newinfo)
MPI_Info MPI_Info_f2c(MPI_Fint info)
MPI_Info_free(info)
int MPI_Info_free(MPI_Info *info)
MPI_Info_get(info, key, valuelen, value, flag)
int MPI_Info_get(MPI_Info info, char *key, int valuelen,
char *value, int *flag)
MPI_Info_get_nkeys(info, nkeys)
int MPI_Info_get_nkeys(MPI_Info info, int *nkeys)
MPI_Info_get_nthkey(info, n, key)
int MPI_Info_get_nthkey(MPI_Info info, int n, char *key)
MPI_Info_get_valuelen(info, key, valuelen, flag)
int MPI_Info_get_valuelen(MPI_Info info, char *key,
int *valuelen, int *flag)
MPI_Info_set(info, key, value)
int MPI_Info_set(MPI_Info info, char *key, char *value)
Fortran:
INCLUDE "mpif.h" (or USE MPI)
INTEGER info, ierror
CALL MPI_INFO_CREATE(info, ierror)
INTEGER info, ierror
CHARACTER*(*) key
CALL MPI_INFO_DELETE(info, key, ierror)
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MPI_Info(3)MPI_Info(3)
INTEGER info, newinfo, ierror
CALL MPI_INFO_DUP(info, newinfo, ierror)
INTEGER info, ierror
CALL MPI_INFO_FREE(info, ierror)
INTEGER info, valuelen, ierror
CHARACTER*(*) key, value
LOGICAL flag
CALL MPI_INFO_GET(info, key, valuelen, value, flag,
ierror)
INTEGER info, nkeys, ierror
CALL MPI_INFO_GET_NKEYS(info, nkeys, ierror)
INTEGER info, n, ierror
CHARACTER*(*) key
CALL MPI_INFO_GET_NTHKEY(info, n, key, ierror)
INTEGER info, valuelen, ierror
LOGICAL flag
CHARACTER*(*) key
CALL MPI_INFO_GET_VALUELEN(info, key, valuelen, flag,
ierror)
INTEGER info, ierror
CHARACTER*(*) key, value
CALL MPI_INFO_SET(info, key, value, ierror)
DESCRIPTION
The following MPI_Info routines allocate memory for MPI arguments:
MPI_Info_c2f Converts information (info) handles from C to
Fortran. The return value is the converted Fortran
info handle.
MPI_Info_create Creates a new info object. The newly created object
contains no (key,value) pairs. MPI_Info_create
accepts the following argument:
info Returns the info object (handle) created.
MPI_Info_delete Deletes a (key,value) pair from info. If key is not
defined in info, the call raises an error of class
MPI_ERR_INFO_NOKEY. MPI_Info_delete accepts the
following arguments:
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MPI_Info(3)MPI_Info(3)
info Indicates and returns the info object (handle).
key Indicates the string to be deleted.
MPI_Info_dup Duplicates an existing info object, creating a new
object with the same (key,value) pairs and the same
ordering of keys. MPI_Info_dup accepts the following
arguments:
info Indicates the info object (handle).
newinfo
Returns the info object (handle).
MPI_Info_f2c Converts info handles from Fortran to C. The return
value is the converted C info handle.
MPI_Info_free Frees the info object and sets it to MPI_INFO_NULL.
The value of an info argument is interpreted each
time the info is passed to a routine. Changes to an
info object after return from a routine do not affect
that interpretation. MPI_Info_free accepts the
following arguments:
info Indicates and returns the info object (handle).
MPI_Info_get Retrieves the value associated with the key in a
previous call to MPI_Info_set. MPI_Info_get accepts
the following arguments:
info Indicates the info object (handle).
key Indicates the key. If this string exists, flag
is set to true and value is returned.
Otherwise, the flag is set to false and value is
left unchanged. If key is larger than
MPI_MAX_INFO_KEY, the call is erroneous.
valuelen
Indicates the length of value. This integer is
the number of characters available in value. If
it is less than the size of value, the value is
truncated. In C, to allow for the null
terminator, valuelen should be one less than the
amount of allocated space.
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value
Returns the value string.
flag Returns true if key is defined, false if not
(boolean).
MPI_Info_get_nkeys Returns the number of currently defined keys in info.
MPI_Info_get_nkeys accepts the following arguments:
info Indicates the info object (handle).
nkeys
Returns the number of defined keys (integer).
MPI_Info_get_nthkey Returns the nth defined key in the info object. Keys
are numbered, where N is the value returned by
MPI_INFO_GET_NKEYS. All keys between 0 and N-1 are
guaranteed to be defined. The number of a given key
does not change as long as info is not modified by
using MPI_INFO_SET or MPI_INFO_DELETE.
MPI_Info_get_nthkey accepts the following arguments:
info Indicates the info object (handle).
n Indicates the key number (integer).
key Returns the key (string).
MPI_Info_get_valuelen
Retrieves the length of the value associated with the
key. If key is defined, valuelen is set to the length
of its associated value and flag is set to true. If
key is not defined, valuelen is not touched and flag
is set to false. The length returned in C or C++ does
not include the end-of-string character. If key is
larger than MPI_MAX_INFO_KEY, the call is erroneous.
MPI_Info_get_valuelen accepts the following
arguments:
info Indicates the info object (handle).
key Indicates the key (string).
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valuelen
Returns the length of the value associated with
the key (integer).
flag Returns true if the key is defined, false if the
key is not defined (boolean).
MPI_Info_set Adds the (key,value) pair to the info object and
overrides the value if a value for the same key was
previously set. In C, key and value are null-
terminated strings. In Fortran, leading and trailing
spaces in key and value are stripped. If either key
or value are larger than the allowed maximums, the
MPI_ERR_INFO_KEY or MPI_ERR_INFO_VALUE errors are
raised, respectively. MPI_Info_set accepts the
following arguments:
info Indicates and returns the info object (handle).
key Indicates the key (string).
value
Indicates the value (string).
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