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 *val);

       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  re‐
       turned by the mmv_lookup_value_desc(3) interface.  addr is the ad‐
       dress returned from mmv_stats_init(3).

       These  interfaces  are  typically used with instantaneous and dis‐
       crete 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 val
       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
       mmv(5).

COLOPHON         top

       This  page is part of the PCP (Performance Co-Pilot) project.  In‐
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Performance Co-Pilot                                     MMV_SET_VALUE(3)

Pages that refer to this page: mmv_inc_value(3)

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