Find a value in the memory mapped value file
#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
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 mmv_stats_init().
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.
The function returns the address inside of the memory mapped region on success or NULL on failure.