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pmdadaemon(3) — Linux manual page

PMDADAEMON(3) Library Functions Manual PMDADAEMON(3)

NAME top

 pmdaDaemon - initialize the PMDA to run as a daemon

C SYNOPSIS top

 #include <pcp/pmapi.h>
 #include <pcp/pmda.h>
 void pmdaDaemon(pmdaInterface *dispatch, int interface,
 const char *name, int domain, const char *logfile,
 const char *helptext);
 cc ... -lpcp_pmda -lpcp

DESCRIPTION top

 pmdaDaemon initializes the pmdaInterface structure to use the in‐
 terface extensions assuming the PMDA(3) is to be run as a daemon.
 The pmdaInterface structure is initialized with:
 name The name of the agent.
 domain The default domain number of the agent which uniquely iden‐
 tifies this PMDA from other running PMDAs. This may be
 subsequently changed by a command line option -d (see
 pmdaGetOpt(3)).
 logfile
 The default path to the log file. This may be replaced by
 the -l command line option if using pmdaGetOpt. logfile
 will be copied with strdup(3), so the storage associated
 with logfile may be released after the call to pmdaDaemon.
 helptext
 The default path to the help text (see pmdaText(3). This
 may be replaced by the -h command line option if using
 pmdaGetOpt(3). If no help text is installed, or you are
 not using pmdaText(3), then this should be set to NULL,
 otherwise helptext will be copied with strdup(3), so the
 storage associated with helptext may be released after the
 call to pmdaDaemon.
 The callbacks are initialized to pmdaProfile(3), pmdaFetch(3),
 pmdaDesc(3), pmdaText(3), pmdaInstance(3) and pmdaStore(3).

CAVEAT top

 The PMDA must be using PMDA_INTERFACE_2 or later.
 Once pmdaDaemon has been called, it is expected that the pmdaIn‐
 terface structure pointed to by dispatch will remain accessible to
 the routines in libpcp_pmda (not reclaimed off the stack, not
 freed or otherwise released, etc.). If the caller needs to move
 or relocate the pmdaInterface structure for any reason, then after
 the move pmdaInterfaceMoved(3) must be called to re-establish the
 internal integrity of the pmdaInterface structure at the new loca‐
 tion before any other routine in libpcp_pmda is called.

DIAGNOSTICS top

 Unable to allocate memory for pmdaExt structure
 In addition, the dispatch->status field is set to a value
 less than zero.
 PMDA interface version interface not supported
 The interface version is not supported by pmdaDaemon.

SEE ALSO top

 PMAPI(3), PMDA(3), pmdaDSO(3), pmdaGetOpt(3),
 pmdaInterfaceMoved(3) and pmdaText(3).

COLOPHON top

 This page is part of the PCP (Performance Co-Pilot) project. In‐
 formation 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
 2025年08月11日. (At that time, the date of the most recent commit
 that was found in the repository was 2025年08月11日.) If you discover
 any rendering problems in this HTML version of the page, or you
 believe there is a better or more up-to-date source for the page,
 or you have corrections or improvements to the information in this
 COLOPHON (which is not part of the original manual page), send a
 mail to man-pages@man7.org
Performance Co-Pilot PCP PMDADAEMON(3)

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Pages that refer to this page: pmda(3), pmdaattribute(3), pmdachildren(3), pmdaconnect(3), pmdadesc(3), pmdadso(3), pmdafetch(3), pmdagetoptions(3), pmdahelp(3), pmdainit(3), pmdainstance(3), pmdainterfacemoved(3), pmdalabel(3), pmdaname(3), pmdaopenlog(3), pmdapmid(3), pmdaprofile(3), pmdastore(3), pmdatext(3)

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