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NAME | C SYNOPSIS | DESCRIPTION | USAGE | DIAGNOSTICS | SEE ALSO | COLOPHON |
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PMPARSETIMEWINDOW(3) Library Functions Manual PMPARSETIMEWINDOW(3)
pmParseTimeWindow, pmParseHighResTimeWindow - parse time window
command line arguments
#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);
int pmParseHighResTimeWindow(const char *swStart,
const char *swEnd, const char *swAlign,
const char *swOffset, const struct timespec *logStart,
const struct timespec *logEnd,
struct timespec *rsltStart, struct timespec *rsltEnd,
struct timespec *rsltOffset, char **errMsg);
cc ... -lpcp
pmParseTimeWindow and pmParseHighResTimeWindow are 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).
pmParseTimeWindow and pmParseHighResTimeWindow expect 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 PM_MAX_TIME_T.
The rsltStart, rsltEnd and rsltOffset structures must be
allocated before calling pmParseTimeWindow or
pmParseTimeHighResWindow.
You also need to set the current PCP reporting time zone to
correctly reflect the -z and -Z command line parameters before
calling these routines. See pmUseZone(3) and friends for
information on how this is done.
If the conversion is successful, pmParseTimeWindow and
pmParseHighResTimeWindow return 1 and fill 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 either pmParseTimeWindow or
pmParseHighResTimeWindow 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 and
pmParseHighResTimeWindow return 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
and pmParseHighResTimeWindow return -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).
free(3), PMAPI(3), pmGetArchiveEnd(3), pmGetArchiveLabel(3),
pmNewContextZone(3), pmNewZone(3), pmParseInterval(3) and
pmUseZone(3).
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 2022-12-17.
(At that time, the date of the most recent commit that was found
in the repository was 2022-12-16.) 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)
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