pmdaText (3) - Linux Manuals

pmdaText: extract metric help text for a PMDA


pmdaText - extract metric help text for a PMDA


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

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

cc ... -lpcp_pmda -lpcp


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.


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


The PMDA must be using PMDA_PROTOCOL_2 or later, as specified in the call to pmdaDSO(3) or pmdaDaemon(3).


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