pmgetarchiveend(3) — Linux manual page

NAME | C SYNOPSIS | DESCRIPTION | PCP ENVIRONMENT | SEE ALSO | DIAGNOSTICS | COLOPHON

PMGETARCHIVEEND(3)      Library Functions Manual      PMGETARCHIVEEND(3)

NAME         top

       pmGetArchiveEnd - locate logical end of file for a set of archive
       logs

C SYNOPSIS         top

       #include <pcp/pmapi.h>

       int pmGetArchiveEnd(struct timeval *tvp);

       cc ... -lpcp

DESCRIPTION         top

       Assuming the current PMAPI context is associated with a set of
       archive logs, pmGetArchiveEnd will attempt to find the logical
       end of file (after the last complete record in the set of
       archives), and return the last recorded timestamp via tvp.  This
       timestamp may be passed to pmSetMode(3) to reliably position the
       context at the last valid log record, e.g. in preparation for
       subsequent reading in reverse chronological order.

       For archive logs that are not concurrently being written, the
       physical end of file and the logical end of file are co-incident.
       However if an archive log is being written by pmlogger(1) at the
       same time an application is trying to read the archive, the
       logical end of file may be before the physical end of file due to
       write buffering that is not aligned with the logical record
       boundaries.

       pmGetArchiveEnd returns an error less than zero if the context is
       neither valid, nor associated with a set of archives, or the set
       of archives is seriously corrupted.  Otherwise, the return value
       is 0 if there has been no change of state since the last call, or
       1 if the logical end of file has advanced since the last call.

       In the absence of an error, the result returned via tvp is well-
       defined.

       pmGetArchiveEnd preserves the positioning state of the log file
       prior to this function call.

PCP ENVIRONMENT         top

       Environment variables with the prefix PCP_ are used to
       parameterize the file and directory names used by PCP.  On each
       installation, the file /etc/pcp.conf contains the local values
       for these variables.  The $PCP_CONF variable may be used to
       specify an alternative configuration file, as described in
       pcp.conf(5).  Values for these variables may be obtained
       programmatically using the pmGetConfig(3) function.

SEE ALSO         top

       PMAPI(3), pmFetch(3), pmFetchArchive(3), pmGetArchiveLabel(3),
       pmGetConfig(3), pmSetMode(3), pcp.conf(5) and pcp.env(5).

DIAGNOSTICS         top

       PM_ERR_NOCONTEXT
              the current PMAPI context is either invalid, or not
              associated with an set of archive logs

       PM_ERR_LOGREC
              the set of archives is sufficiently damaged, that not a
              single valid record can be found

COLOPHON         top

       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 2020-12-18.
       (At that time, the date of the most recent commit that was found
       in the repository was 2020-12-18.)  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                PMGETARCHIVEEND(3)

Pages that refer to this page: __pmparsetime(3)pmparsetimewindow(3)