pmdahelp(3) — Linux manual page
PMDAHELP(3) Library Functions Manual PMDAHELP(3)
NAME
pmdaOpenHelp, pmdaGetHelp, pmdaGetInDomHelp, pmdaCloseHelp - help
text support for a PMDA
C SYNOPSIS
#include <pcp/pmapi.h>
#include <pcp/pmda.h>
int pmdaOpenHelp(const char *fname);
char *pmdaGetHelp(int handle, pmID pmid, int type);
char *pmdaGetInDomHelp(int handle, pmInDom indom, int type);
void pmdaCloseHelp(int handle);
cc ... -lpcp_pmda -lpcp
DESCRIPTION
As part of the Performance Metrics Domain Agent (PMDA) API (see
PMDA(3)), this group of routines is used to implement the
processing of a PMDA's metric help information.
These routines are really intended for internal use, and should
not need to be called directly from any PMDA code.
Briefly, the base name of the help text file (as created by
newhelp(1)) is passed in via a -h command line option for a
daemon PMDA or as an argument to pmdaDaemon(3) or pmdaDSO(3).
Then pmdaOpenHelp is called from pmdaInit(3) and returns a handle
that is used in subsequent calls to identify a particular help
text collection (each PMDA typically has only one such
collection).
Requests for help text are passed to pmdaText(3) which calls
pmdaGetHelp or pmdaGetInDomHelp as required.
Other than error cases in pmdaOpenHelp, pmdaCloseHelp is not
called.
CAVEAT
The PMDA must be using PMDA_INTERFACE_2 or later, as specified in
the call to pmdaDSO(3) or pmdaDaemon(3).
DIAGNOSTICS
pmdaOpenHelp returns a negative value for failure, suitable for
decoding with pmErrStr(3). pmdaGetHelp and pmdaGetInDomHelp
return NULL if the corresponding help text does not exist.
SEE ALSO
newhelp(1), PMAPI(3), PMDA(3), pmdaDaemon(3), pmdaDSO(3),
pmdaInit(3), pmdaText(3) and pmErrStr(3).
COLOPHON
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@groups.io. This page was obtained from the
project's upstream Git repository
⟨https://github.com/performancecopilot/pcp.git⟩ on 2024-06-14.
(At that time, the date of the most recent commit that was found
in the repository was 2024-06-14.) If you discover any rendering
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