pmParseTimeWindow - parse time window command line arguments
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
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).
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 PCP archive log 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
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.
PMAPI(3), pmGetArchiveEnd(3), pmGetArchiveLabel(3),
pmNewContextZone(3), pmNewZone(3), pmParseInterval(3) and pmUseZone(3).
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 PCP archive log 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 an internal static buffer. This buffer should not
If the argument strings could not be parsed, pmParseTimeWindow returns
-1. In this case, errMsg will point to an error message in a static