NAME | C SYNOPSIS | DESCRIPTION | EXAMPLES | RETURN VALUE | SEE ALSO | COLOPHON |
PMPARSEUNITSSTR(3) Library Functions Manual PMPARSEUNITSSTR(3)
pmParseUnitsStr - parse units specification
#include <pcp/pmapi.h> int pmParseUnitsStr(const char *string, struct pmUnits *out, double *outMult, char **errMsg); cc ... -lpcp
pmParseUnitsStr is designed to encapsulate the interpretation of a units (dimension and scale) specification in command line switches for use by the PCP client tools. This function expects to be called with the unit/scale specification as string. This specification takes the general form produced by pmUnitsStr. Briefly, the format allows /-separated divisor and dividend, each listing space-separated dimensions/scales along the space, time, and count axes. There are also a few extra possibilities: First, multiple equivalent sets of keywords are accepted for the time & space dimensions, insensitive to case. For example, "microseconds", "microsecond", "microsec", "us" are considered synonymous, as are "kilobytes", "KB", "kiloByte", and so on. Second, units may be offered in any order, e.g., ms kb count x 10^3 or count x 10^3 kb ms. They may not be repeated within the denominator or within the numerator. Each scale/unit keyword may be immediately followed by positive or negative exponents, e.g., ^-4. Third, numerical scaling factors may be supplied. These are factored together with implicit scale conversions into the final outMult result. The out and outMult values must both be allocated before calling pmParseUnitsStr. If the conversion is successful, pmParseUnitsStr returns 0, and fills in out and outMult with the unit/scales defined by the input parameter. If the argument strings could not be parsed, it returns a negative status code.
┌──────────────────────────────────┬────────────────┬─────────┐ │ string │ out │ outMult │ ├──────────────────────────────────┼────────────────┼─────────┤ │2 count │ {0,1,0,0,0,0} │ 0.5 │ │count / 7.5 nanosecond │ {0,1,-1,0,0,0} │ 7.5 │ │10 kilobytes / 2.5e2 count x 10^3 │ {1,-1,0,1,3,0} │ 25 │ │millisecond / second^2 │ {0,0,-1,0,0,3} │ 1000 │ │mb/s │ {1,0,-1,2,0,3} │ 1 │ └──────────────────────────────────┴────────────────┴─────────┘
A zero status indicates success. A negative status indicates an error, in which case the errMsg pointer will receive a textual error message, which the caller should later free().
PMAPI(3), pmUnitsStr(3), pmConvScale(3), and pmLookupDesc(3).
This page is part of the PCP (Performance Co-Pilot) project.
Information about the project can be found at ⟨http://www.pcp.io/⟩.
If you have a bug report for this manual page, send it to
pcp@oss.sgi.com. This page was obtained from the project's upstream
Git repository ⟨git://git.pcp.io/pcp⟩ on 2017-07-05. If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page, or
you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a mail
to man-pages@man7.org
Performance Co-Pilot PCP PMPARSEUNITSSTR(3)
Pages that refer to this page: pcp2graphite(1), pcp2influxdb(1), pmdaprometheus(1), pmrep(1), pmfetchgroup(3), pmregisterderived(3)