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
       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

       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.

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
       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 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.