pmparsetimewindow(3) — Linux manual page

NAME | C SYNOPSIS | DESCRIPTION | USAGE | DIAGNOSTICS | SEE ALSO | COLOPHON

PMPARSETIMEWINDOW(3)    Library Functions Manual    PMPARSETIMEWINDOW(3)

NAME         top

       pmParseTimeWindow - parse time window command line arguments

C SYNOPSIS         top

       #include <pcp/pmapi.h>

       int pmParseTimeWindow(const char *swStart, const char *swEnd,
               const char *swAlign, const char *swOffset,
               const struct timeval *logStart,
               const struct timeval *logEnd, struct timeval *rsltStart,
               struct timeval *rsltEnd, struct timeval *rsltOffset,
               char **errMsg);

       cc ... -lpcp

DESCRIPTION         top

       pmParseTimeWindow is designed to encapsulate the interpretation
       of the -S, -T, -A and -O command line options used by Performance
       Co-Pilot (PCP) applications to define a time window of interest.
       The time window is defined by a start time and an end time that
       constrains the time interval during which the PCP application
       will retrieve and display performance metrics.  In the absence of
       the -O and -A options to specify an initial sample time origin
       and time alignment (see below), the PCP application will retrieve
       the first sample at the start of the time window.

       The syntax and meaning of the various argument formats for these
       options is described in PCPIntro(1).

USAGE         top

       pmParseTimeWindow expects to be called with the argument of the
       -S option as swStart, the argument of the -T option as swEnd, the
       argument of the -A option as swAlign, and the argument of the -O
       option as swOffset.  Any or all of these parameters may be NULL
       to indicate that the corresponding command line option was not
       present.

       If the application is using a set of PCP archive logs as the
       source of performance metrics, you also need to supply the time
       of the first archive log entry as logStart, and the time of the
       last archive log entry as logEnd.  See pmGetArchiveLabel(3) and
       pmGetArchiveEnd(3) for how to obtain values for these times.

       If the application is manipulating multiple concurrent archive
       logs, then the caller must resolve how the default time window is
       to be defined (the union of the time intervals in all archive
       logs is a likely interpretation).

       If the application is using a live feed of performance data,
       logStart should be the current time (but could be aligned on the
       next second for example), while logEnd should have its tv_sec
       component set to INT_MAX.

       The rsltStart, rsltEnd and rsltOffset structures must be
       allocated before calling pmParseTimeWindow.

       You also need to set the current PCP reporting time zone to
       correctly reflect the -z and -Z command line parameters before
       calling pmParseTimeWindow.  See pmUseZone(3) and friends for
       information on how this is done.

DIAGNOSTICS         top

       If the conversion is successful, pmParseTimeWindow returns 1 and
       fills in rsltStart, rsltEnd and rsltOffset with the start, end,
       and offset times for the time window defined by the input
       parameters.  The errMsg parameter is not changed when
       pmParseTimeWindow returns 1.

       If the conversion is successful, but the requested alignment
       could not be performed (e.g. the set of PCP archive logs is too
       short) the alignment is ignored, rsltStart, rsltEnd and
       rsltOffset are filled in and pmParseTimeWindow returns 0.  In
       this case, errMsg will point to a warning message in a
       dynamically allocated buffer.  The caller is responsible for
       releasing the buffer by calling free(3).

       If the argument strings could not be parsed, pmParseTimeWindow
       returns -1.  In this case, errMsg will point to an error message
       in a dynamically allocated buffer.  The caller is responsible for
       releasing the buffer by calling free(3).

SEE ALSO         top

       free(3), PMAPI(3), pmGetArchiveEnd(3), pmGetArchiveLabel(3),
       pmNewContextZone(3), pmNewZone(3), pmParseInterval(3) and
       pmUseZone(3).

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 2021-08-27.
       (At that time, the date of the most recent commit that was found
       in the repository was 2021-08-27.)  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              PMPARSETIMEWINDOW(3)

Pages that refer to this page: pmseries(1)__pmconverttime(3)pmparseinterval(3)__pmparsetime(3)