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pmdatext(3) [centos man page]

PMDATEXT(3)						     Library Functions Manual						       PMDATEXT(3)

NAME
pmdaText - extract metric help text for a PMDA C SYNOPSIS
#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 DESCRIPTION
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. DIAGNOSTICS
If the requested help text could not be obtained, pmdaText will return PM_ERR_TEXT. CAVEAT
The PMDA must be using PMDA_PROTOCOL_2 or later, as specified in the call to pmdaDSO(3) or pmdaDaemon(3). SEE ALSO
newhelp(1), malloc(3), PMAPI(3), PMDA(3), pmdaDaemon(3), pmdaDSO(3), pmdaInit(3), pmLookupInDomText(3) and pmLookupText(3). Performance Co-Pilot PCP PMDATEXT(3)

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PMDAGETOPT(3)						     Library Functions Manual						     PMDAGETOPT(3)

NAME
pmdaGetOpt - get options from argument vector, trapping generic PMDA options C SYNOPSIS
#include <pcp/pmapi.h> #include <pcp/impl.h> #include <pcp/pmda.h> int pmdaGetOpt(int argc, char *const *argv, const char *optstring, pmdaInterface *dispatch, int *err); cc ... -lpcp_pmda -lpcp DESCRIPTION
This function is a wrapper for getopt(3). The behavior of the function is identical except that certain options are assumed to have a pre- defined behavior which initializes several fields in the pmdaInterface structure. The options that pmdaGetOpt will trap are: -Dtrace Set the PMAPI(3) debug control variable (pmDebug) to trace. Used for controlling levels of trace output while debugging. -ddomain Set the domain number of this agent. -hhelpfile Obtain the help text (see pmdaText(3)) for the metrics from this file rather than from the path specified with pmdaDSO(3) or pmdaDaemon(3). -iport Expect PMCD to connect on inet port (number or name). -6port Expect PMCD to connect on ipv6 port (number or name). -llogfile Redirect diagnostics and trace output to logfile. -p Expect PMCD to supply stdin/stdout pipe. -usocket Expect PMCD to connect on unix domain socket. Only one of -i, -6, -p and -u may be specified. If none of these three options is given, a pipe (-p) is assumed. When these options are encountered by pmdaGetOpt, the option is processed and the next option is examined. Therefore, pmdaGetOpt will only return when an option other than those listed above is found, or the end of the list is reached. The returned value will be the argument or EOF, respectively. A PMDA can control which of these options the program will accept with the optstring argument. To accept all the options, the PMDA should call pmdaGetOpt with the option string "D:d:h:i:l:pu:". Any PMDA specific options should be added to this string in the style of getopt(3), and returned by pmdaGetOpt if encountered. However, the PMDA cannot reuse any of the options specified above. pmdaGetOpt takes a pointer to an int, err, which is used as an error count. This variable should be initialized to zero before pmdaGetOpt is first called, and tested when pmdaGetOpt returns EOF. pmdaGetOpt does not modify argc or argv. EXAMPLE
A PMDA which takes the additional argument -n and does not use pmDebug might call pmdaGetOpt like this: pmdaInterface dispatch; int err = 0; int c = 0; while ((c = pmdaGetOpt(argv, argc, "d:h:i:l:pu:6:n:", dispatch &err)) != EOF) { /* process argument 'n', may use optarg etc. */ } if (err) usage(argv[0]); The global variables used by getopt (3) may be used by the caller of pmdaGetOpt within the argument parsing loop. DIAGNOSTICS
pmdaGetOpt will display the same error messages as getopt. CAVEAT
The options -D, -d, -i, -l, -p and -u cannot be reused for other purposes by the PMDA. The PMDA must be using PMDA_INTERFACE_2 or later, as specified in the call to pmdaDSO(3) or pmdaDaemon(3). SEE ALSO
pmdbg(1), getopt(3), PMAPI(3), PMDA(3), pmdaDaemon(3), pmdaDSO(3) and pmdaText(3). Performance Co-Pilot PCP PMDAGETOPT(3)

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