pmdatext(3) — Linux manual page


PMDATEXT(3)             Library Functions Manual             PMDATEXT(3)

NAME         top

       pmdaText - extract metric help text for a PMDA

C SYNOPSIS         top

       #include <pcp/pmapi.h>
       #include <pcp/pmda.h>

       int pmdaText(int ident, int type, char **buffer, pmdaExt *pmda);

       cc ... -lpcp_pmda -lpcp

DESCRIPTION         top

       As part of the Performance Metrics Domain Agent (PMDA) API (see
       PMDA(3)), pmdaText uses the standard PMDA(3) data structures to
       return the help text for metric ident in buffer.  The help text
       must be located in help text files created with newhelp(1), and
       the associated files are automatically opened by pmdaInit(3).

       The path to the (basename of the) help text files can be set in
       the calls to pmdaDSO(3) or pmdaDaemon(3) and overridden by the -h
       command line option in pmdaGetOpt(3).

       The encoding of ident follows the internal scheme used below the
       routines pmLookupText(3) and pmLookupInDomText(3), namely ident
       encodes either a metric identifier or an instance domain
       identifier, according to the value of type.

       The type argument is a bit mask that encodes the interpretation
       of ident and the requested form of help text, as follows: either
       PM_TEXT_PMID if ident is a metric identifier, or PM_TEXT_INDOM if
       ident is an instance domain identifier, plus either
       PM_TEXT_ONELINE for the one line help text or PM_TEXT_HELP for
       the full help text.

       The buffer is managed internally (usually it is cached), and it
       should not be released or freed by the caller of pmdaText.

CAVEAT         top

       The PMDA must be using PMDA_INTERFACE_2 or later, as specified in
       the call to pmdaDSO(3) or pmdaDaemon(3).

DIAGNOSTICS         top

       If the requested help text could not be obtained, pmdaText will
       return PM_ERR_TEXT.

SEE ALSO         top

       newhelp(1), malloc(3), PMAPI(3), PMDA(3), pmdaDaemon(3),
       pmdaDSO(3), pmdaInit(3), pmLookupInDomText(3) and

COLOPHON         top

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Performance Co-Pilot               PCP                       PMDATEXT(3)

Pages that refer to this page: pmda(3)pmdadaemon(3)pmdadso(3)pmdagetoptions(3)pmdahelp(3)pmdainit(3)pmdamain(3)