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