преобразовать единицы измерения производительности в строку (convert a performance metric's units into a string)
Имя (Name)
pmUnitsStr, pmUnitsStr_r - convert a performance metric's units
into a string
Синопсис C (C Synopsis)
#include <pcp/pmapi.h>
const char *pmUnitsStr(const pmUnits *pu);
char *pmUnitsStr_r(const pmUnits *pu, char *buf, int buflen);
cc ... -lpcp
Описание (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.
Примечание (Note)
pmUnitsStr returns a pointer to a static buffer and hence is not
thread-safe. Multi-threaded applications should use pmUnitsStr_r
instead.
Смотри также (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).
