PMUNITSSTR(3)              Library Functions Manual              PMUNITSSTR(3)

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, e.g.
       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).

Performance Co-Pilot                  PCP                        PMUNITSSTR(3)