NAME

       msr_starttime - Start and end time determination for MSRecord structures

SYNOPSIS

       #include <libmseed.h>

       hptime_t  msr_starttime ( MSRecord *msr );

       hptime_t  msr_starttime_uc ( MSRecord *msr );

       hptime_t  msr_endtime ( MSRecord *msr );

DESCRIPTION

       msr_starttime  returns  the  start  time of the record as a high precision epoch time (see
       ms_time(3)).  Any time correction given in the fixed section data header is applied if  it
       has  not  already been applied.  If Blockette 1001 is included and parsed the microseconds
       indicated (field 4) are also applied.

       NOTE:  The  record  start  time  for  a  MSRecord  structure  is  available  directly   at
       MSRecord.starttime.   Libmseed based programs should use that start time whenever possible
       (msr_unpack uses msr_starttime to set MSRecord.starttime).

       msr_starttime_uc is a version of msr_starttime that applies no time  corrections,  just  a
       basic conversion of the start time values in the fixed section data header.

       msr_endtime  returns  the  time of the last sample in the record as a high precision epoch
       time (seed ms_time(3)).  This is *not* the time "covered" by  the  last  sample,  but  the
       actual sample time.  This function calculates the record start time with msr_starttime and
       then adds the time covered by the samples in the  record  which  is  calculated  from  the
       number of samples and sample rate.

       msr_endtime  will  adjust  the  end time appropriately if the record is known to contain a
       positive leap second.  If the ms_readleapseconds or  ms_readleapsecondfile  routines  have
       been  called  to read a leap second file into an internal list, it will be checked to know
       when leap seconds occur.  If a leap second list is not available the  fixed  section  data
       header is checked for a positive leap second indicator.

RETURN VALUES

       msr_starttime,  msr_starttime_uc  and  msr_endtime  return  a high precision epoch time on
       success and HPTERROR on error.

SEE ALSO

       ms_intro(3), ms_time(3) and msr_unpack(3)

AUTHOR

       Chad Trabant
       IRIS Data Management Center