PMATOMSTR(3)						     Library Functions Manual						      PMATOMSTR(3)

NAME

       pmAtomStr, pmAtomStr_r - convert a performance metric value into a string

C SYNOPSIS

       #include <pcp/pmapi.h>

       const char *pmAtomStr(const pmAtomValue *avp, int type);
       char *pmAtomStr_r(const pmAtomValue *avp, int type, char *buf, int buflen);

       cc ... -lpcp

DESCRIPTION

       All performance metric values may be encoded in a pmAtomValue union, 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;

       Given  the  performance	metric	value pointed to by avp, and a performance metric type defined by type, pmAtomStr will generate the corre-
       sponding metric value as a string, suitable for diagnostic or report output.  The pmAtomStr_r function does the same, but stores the result
       in a user-supplied buffer buf of length buflen, which should have room for at least 80 bytes.

       The value for type is typically extracted from a pmDesc structure, following a call to pmLookupDesc(3) for a particular performance metric.

       If  the	type  is PM_TYPE_STRING values longer than 38 characters will be truncated after 34 characters, and truncation shown with ellipsis
       ``...'' at the end of the value.

       If the type is PM_TYPE_AGGREGATE then up to the first three 32-bit words are displayed as hexadecimal values.

       If the type is PM_TYPE_EVENT then a summary of the number of event records found in the value is generated.

       The return value from pmAtomStr is held in a single static buffer, so the returned value is only valid until the next call to pmAtomStr.

NOTES

       pmAtomStr returns a pointer to a static buffer and hence is not thread-safe.  Multi-threaded applications should use pmAtomStr_r instead.

SEE ALSO

       PMAPI(3), pmConvScale(3), pmExtractValue(3), pmLookupDesc(3), pmPrintValue(3), pmTypeStr(3) and pmUnitsStr(3).

Performance Co-Pilot							PCP							      PMATOMSTR(3)