mmv_lookup_value_desc(3) — Linux manual page


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

NAME         top

       mmv_lookup_value_desc - find a value in the Memory Mapped Value

C SYNOPSIS         top

       #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         top

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

       The pointer returned points to a pmAtomValue union, which is
       defined 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         top

       The function returns the address inside of the memory mapped
       region on success or NULL on failure.

SEE ALSO         top

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

COLOPHON         top

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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)