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NAME | C SYNOPSIS | DESCRIPTION | USAGE | DIAGNOSTICS | COMPATIBILITY | SEE ALSO | COLOPHON |
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PMPARSETIMEWINDOW(3) Library Functions Manual PMPARSETIMEWINDOW(3)
pmParseTimeWindow - 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 timespec *logStart,
const struct timespec *logEnd,
struct timespec *rsltStart,
struct timespec *rsltEnd,
struct timespec *rsltOffset, char **errMsg);
cc ... -lpcp
pmParseTimeWindow 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 expect to be called with the argument of the -S
option as swStart, the argument of the -T option as swEnd, the ar‐
gument of the -A option as swAlign, and the argument of the -O op‐
tion 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 archives as the source of
performance metrics, you also need to supply the time of the first
archive entry as logStart, and the time of the last archive entry
as logEnd. See pmGetArchiveLabel(3) and pmGetArchiveEnd(3) for
how to obtain values for these times.
If the application is manipulating multiple concurrent archives,
then the caller must resolve how the default time window is to be
defined (the union of the time intervals in all archives 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 com‐
ponent set to PM_MAX_TIME_T.
The rsltStart, rsltEnd and rsltOffset structures must be allocated
before calling pmParseTimeWindow.
You also need to set the current PCP reporting time zone to cor‐
rectly reflect the -z and -Z command line parameters before call‐
ing these routines. See pmUseZone(3) and friends for information
on how this is done.
If the conversion is successful, pmParseTimeWindow 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
returns 1.
If the conversion is successful, but the requested alignment could
not be performed (e.g. the set of PCP archives is too short) the
alignment is ignored, rsltStart, rsltEnd and rsltOffset are filled
in and pmParseTimeWindow 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 re‐
turn -1. In this case, errMsg will point to an error message in a
dynamically allocated buffer. The caller is responsible for re‐
leasing the buffer by calling free(3).
Prior to PCP 7.0 and libpcp.so.4 the logStart, logEnd, rsltStart,
rsltEnd and rsltOffset arguments were struct timeval. To support
PMAPI transition, the old interface and semantics can be used if
applications are linked with libpcp.so.3 or recompiled with
-DPMAPI_VERSION=2.
For a time in PCP 6.x there was a routine with the same semantics
as the current pmParseTimeWindow called pmParseHighResTimeWindow
although this is now deprecated and compile-time support for pm‐
ParseHighResTimeWindow will be removed in a future release.
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. 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
2025-08-11. (At that time, the date of the most recent commit
that was found in the repository was 2025-08-11.) 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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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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