NAME

       pmParseTimeWindow - parse time window command line arguments

C SYNOPSIS

       #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

       pmParseTimeWindow is designed to encapsulate the interpretation of the -S, -T, -A and -O command line op‐
       tions used by Performance Co-Pilot (PCP) applications to define a time window of interest.  The time win‐
       dow is defined by a start time and an end time that constrains the time interval during which the PCP ap‐
       plication  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

       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 swOff‐
       set.   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 sup‐
       ply 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 in‐
       terpretation).

       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.

SEE ALSO

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

DIAGNOSTICS

       If the conversion is successful, pmParseTimeWindow returns 1 and fills in rsltStart, rsltEnd and rsltOff‐
       set with the start, end, and offset times for the time window defined by the input parameters.   The  er‐
       rMsg 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 pmParse‐
       TimeWindow returns 0.  In this case, errMsg will point to a warning message in an internal static buffer.
       This buffer should not be freed.

       If the argument strings could not be parsed, pmParseTimeWindow returns -1.  In  this  case,  errMsg  will
       point to an error message in a static internal buffer.

Performance Co-Pilot                                   PCP                                  PMPARSETIMEWINDOW(3)