mmv_lookup_value_desc(3) — Linux manual page

MMV_LOOK...ALUE_DESC(3) Library Functions Manual MMV_LOOK...ALUE_DESC(3)

NAME

       mmv_lookup_value_desc - find a value in the Memory Mapped Value
       file

C SYNOPSIS

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

       pmAtomValue *mmv_lookup_value_desc(void *addr, const char
               *metric, const char *inst);

       cc ... -lpcp_mmv -lpcp

DESCRIPTION

       mmv_lookup_value_desc  searches  for  the  value  of the instance
       identified by the external instance name inst of the metric  met‐
       ric  in  the  MMV(5)  file.   addr  is  the address returned from
       mmv_stats_init().

       The pointer returned points to a pmAtomValue union, which is  de‐
       fined as follows:

           typedef union {
               __int32_t   l;      /* 32-bit signed */
               __uint32_t  ul;     /* 32-bit unsigned */
               __int64_t   ll;     /* 64-bit signed */
               __uint64_t  ull;    /* 64-bit unsigned */
               float       f;      /* 32-bit floating point */
               double      d;      /* 64-bit floating point */
               char         *cp;   /* char ptr */
            pmValueBlock *vbp;  /* pmValueBlock ptr */
           } pmAtomValue;

       MMV   string   values   should   be   set  using  either  of  the
       mmv_set_string or mmv_set_strlen routines.

RETURNS

       The function returns the address inside of the memory mapped  re‐
       gion on success or NULL on failure.

SEE ALSO

       mmv_stats_init(3), mmv_inc_value(3) and mmv(5).

COLOPHON

       This page is part of the PCP (Performance Co-Pilot) project.  In‐
       formation about the project can be found at ⟨http://www.pcp.io/⟩.
       If  you  have  a  bug  report  for  this  manual page, send it to
       pcp@groups.io.   This  page  was  obtained  from  the   project's
       upstream                      Git                      repository
       ⟨https://github.com/performancecopilot/pcp.git⟩  on   2024-06-14.
       (At  that time, the date of the most recent commit that was found
       in the repository was 2024-06-14.)  If you discover any rendering
       problems in this HTML version of the page, or you  believe  there
       is  a  better or more up-to-date source for the page, or you have
       corrections or improvements to the information in  this  COLOPHON
       (which  is  not part of the original manual page), send a mail to
       man-pages@man7.org

Performance Co-Pilot                             MMV_LOOK...ALUE_DESC(3)

Pages that refer to this page: mmv_inc_value(3), mmv_set_value(3), mmv_stats_init(3), mmv_stats_registry(3)

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