mmv_set_value(3) — Linux manual page


MMV_SET_VALUE(3)        Library Functions Manual        MMV_SET_VALUE(3)

NAME         top

       mmv_set, mmv_set_value, mmv_set_atomvalue - set a value in a
       Memory Mapped Value file

C SYNOPSIS         top

       #include <pcp/pmapi.h>
       #include <pcp/mmv_stats.h>

       void mmv_set(void *addr, pmAtomValue *av, void *val);
       void mmv_set_value(void *addr, pmAtomValue *av, double val);
       void mmv_set_atomvalue(void *addr, pmAtomValue *av, pmAtomValue

       cc ... -lpcp_mmv -lpcp

DESCRIPTION         top

       mmv_set, mmv_set_value and mmv_set_atomvalue provide convenient
       ways of directly setting a value for a metric av previously
       returned by the mmv_lookup_value_desc(3) interface.  addr is the
       address returned from mmv_stats_init(3).

       These interfaces are typically used with instantaneous and
       discrete metrics.  Refer to mmv_inc_value(3) for a mechanism
       suited to monotonic increasing counter metrics.

       With mmv_set and mmv_set_atomvalue the value provided via the inc
       pointer must match the type of the metric and will be used as the
       new value of the metric.

       In the case of mmv_set and mmv_set_value, the pointer value val
       is internally cast to match the type of the metric and then used
       as the value for the metric.

SEE ALSO         top

       mmv_inc_value(3), mmv_stats_init(3), mmv_lookup_value_desc(3) and

COLOPHON         top

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Performance Co-Pilot                                    MMV_SET_VALUE(3)

Pages that refer to this page: mmv_inc_value(3)