.TH "hwlocality_distances_add" 3 "Mon Oct 7 2024" "Version 2.11.2" "Hardware Locality (hwloc)" \" -*- nroff -*-
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.SH NAME
hwlocality_distances_add \- Add distances between objects
.SH SYNOPSIS
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.PP
.SS "Typedefs"

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.RI "typedef void * \fBhwloc_distances_add_handle_t\fP"
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.SS "Enumerations"

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.RI "enum \fBhwloc_distances_add_flag_e\fP { \fBHWLOC_DISTANCES_ADD_FLAG_GROUP\fP, \fBHWLOC_DISTANCES_ADD_FLAG_GROUP_INACCURATE\fP }"
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.SS "Functions"

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.RI "\fBhwloc_distances_add_handle_t\fP \fBhwloc_distances_add_create\fP (\fBhwloc_topology_t\fP topology, const char *name, unsigned long kind, unsigned long flags)"
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.RI "int \fBhwloc_distances_add_values\fP (\fBhwloc_topology_t\fP topology, \fBhwloc_distances_add_handle_t\fP handle, unsigned nbobjs, \fBhwloc_obj_t\fP *objs, hwloc_uint64_t *values, unsigned long flags)"
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.RI "int \fBhwloc_distances_add_commit\fP (\fBhwloc_topology_t\fP topology, \fBhwloc_distances_add_handle_t\fP handle, unsigned long flags)"
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.SH "Detailed Description"
.PP 
The usual way to add distances is: 
.PP
.nf
hwloc_distances_add_handle_t handle;
int err = -1;
handle = hwloc_distances_add_create(topology, "name", kind, 0);
if (handle) {
  err = hwloc_distances_add_values(topology, handle, nbobjs, objs, values, 0);
  if (!err)
    err = hwloc_distances_add_commit(topology, handle, flags);
}

.fi
.PP
 If \fCerr\fP is \fC0\fP at the end, then addition was successful\&. 
.SH "Typedef Documentation"
.PP 
.SS "typedef void* \fBhwloc_distances_add_handle_t\fP"

.PP
Handle to a new distances structure during its addition to the topology\&. 
.SH "Enumeration Type Documentation"
.PP 
.SS "enum \fBhwloc_distances_add_flag_e\fP"

.PP
Flags for adding a new distances to a topology\&. 
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\fBEnumerator\fP
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.TP
\fB\fIHWLOC_DISTANCES_ADD_FLAG_GROUP \fP\fP
Try to group objects based on the newly provided distance information\&. Grouping is only performed when the distances structure contains latencies, and when all objects are of the same type\&. 
.TP
\fB\fIHWLOC_DISTANCES_ADD_FLAG_GROUP_INACCURATE \fP\fP
If grouping, consider the distance values as inaccurate and relax the comparisons during the grouping algorithms\&. The actual accuracy may be modified through the HWLOC_GROUPING_ACCURACY environment variable (see \fBEnvironment Variables\fP)\&. 
.SH "Function Documentation"
.PP 
.SS "int hwloc_distances_add_commit (\fBhwloc_topology_t\fP topology, \fBhwloc_distances_add_handle_t\fP handle, unsigned long flags)"

.PP
Commit a new distances structure\&. This function finalizes the distances structure and inserts in it the topology\&.
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Parameter \fChandle\fP was previously returned by \fBhwloc_distances_add_create()\fP\&. Then objects and values were specified with \fBhwloc_distances_add_values()\fP\&.
.PP
\fCflags\fP configures the behavior of the function using an optional OR'ed set of \fBhwloc_distances_add_flag_e\fP\&. It may be used to request the grouping of existing objects based on distances\&.
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On error, the temporary distances structure and its content are destroyed\&.
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\fBReturns\fP
.RS 4
0 on success\&. 
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-1 on error\&. 
.RE
.PP

.SS "\fBhwloc_distances_add_handle_t\fP hwloc_distances_add_create (\fBhwloc_topology_t\fP topology, const char * name, unsigned long kind, unsigned long flags)"

.PP
Create a new empty distances structure\&. Create an empty distances structure to be filled with \fBhwloc_distances_add_values()\fP and then committed with \fBhwloc_distances_add_commit()\fP\&.
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Parameter \fCname\fP is optional, it may be \fCNULL\fP\&. Otherwise, it will be copied internally and may later be freed by the caller\&.
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\fCkind\fP specifies the kind of distance as a OR'ed set of \fBhwloc_distances_kind_e\fP\&. Only one kind of meaning and one kind of provenance may be given if appropriate (e\&.g\&. \fBHWLOC_DISTANCES_KIND_MEANS_BANDWIDTH\fP and \fBHWLOC_DISTANCES_KIND_FROM_USER\fP)\&. Kind \fBHWLOC_DISTANCES_KIND_HETEROGENEOUS_TYPES\fP will be automatically set according to objects having different types in \fBhwloc_distances_add_values()\fP\&.
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\fCflags\fP must be \fC0\fP for now\&.
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\fBReturns\fP
.RS 4
A hwloc_distances_add_handle_t that should then be passed to \fBhwloc_distances_add_values()\fP and \fBhwloc_distances_add_commit()\fP\&.
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\fCNULL\fP on error\&. 
.RE
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.SS "int hwloc_distances_add_values (\fBhwloc_topology_t\fP topology, \fBhwloc_distances_add_handle_t\fP handle, unsigned nbobjs, \fBhwloc_obj_t\fP * objs, hwloc_uint64_t * values, unsigned long flags)"

.PP
Specify the objects and values in a new empty distances structure\&. Specify the objects and values for a new distances structure that was returned as a handle by \fBhwloc_distances_add_create()\fP\&. The structure must then be committed with \fBhwloc_distances_add_commit()\fP\&.
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The number of objects is \fCnbobjs\fP and the array of objects is \fCobjs\fP\&. Distance values are stored as a one-dimension array in \fCvalues\fP\&. The distance from object i to object j is in slot i*nbobjs+j\&.
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\fCnbobjs\fP must be at least 2\&.
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Arrays \fCobjs\fP and \fCvalues\fP will be copied internally, they may later be freed by the caller\&.
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On error, the temporary distances structure and its content are destroyed\&.
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\fCflags\fP must be \fC0\fP for now\&.
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\fBReturns\fP
.RS 4
0 on success\&. 
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-1 on error\&. 
.RE
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.SH "Author"
.PP 
Generated automatically by Doxygen for Hardware Locality (hwloc) from the source code\&.