NAME

       pmUnitsStr, pmUnitsStr_r - convert a performance metric's units into a string

C SYNOPSIS

       #include <pcp/pmapi.h>

       const char *pmUnitsStr(const pmUnits *pu);
       char *pmUnitsStr_r(const pmUnits *pu, char *buf, int buflen);

       cc ... -lpcp

DESCRIPTION

       The  encoding of a performance metric's dimensionality and scale uses a pmUnits structure;
       see pmLookupDesc(3).

       As an aid to labeling graphs and tables, or for error messages,  pmUnitsStr  will  take  a
       dimension  and  scale  specification  as per pu, and return the corresponding text string.
       The pmUnitsStr_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 60 bytes.  If buflen is less
       than 60 then pmUnitsStr_r returns NULL and buf is not changed.

       For example {1, -2, 0, PM_SPACE_MBYTE, PM_TIME_SEC, 0}, as the  value  of  *pu  gives  the
       result string Mbyte / sec^2.

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

       If the ``count'' dimension is non-zero, and the ``count'' scale is not zero, then the text
       string will include a decimal scaling factor, eg.  count x 10^6.

       As  a  special case, if all components of the dimension are zero, then the ``count'' scale
       is used to produce the text.  If this scale  is  zero  the  result  is  an  empty  string,
       otherwise the result is of the form x1 0^2.

NOTES

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

SEE ALSO

       PMAPI(3),    pmAtomStr(3),     pmConvScale(3),     pmExtractValue(3),     pmLookupDesc(3),
       pmPrintValue(3), pmIDStr(3), pmInDomStr(3), pmTypeStr(3), pmSemStr(3) and pmUnitsStr(3).