Release Notes:  Earthworm Version "V6.2"

NEW MODULES:
***********

FOR AUTOMATIC EARTHWORM:

File-based exchange system:
A file-based data exchange system is now available, consisting of the modules
ew2file, sendfileII, getfileII and file2ew. The module ew2file reads selected
messages from an Earthworm ring and writes these messages to disk files in one
or more directories. The files are picked up from a directory by sendfileII,
which transmits the files over the network to a host running getfileII. The
getfileII program accepts connections from one or more hosts running
sendfileII, and places the incoming files in the directory assigned to the
sending address. Finally, file2ew picks up files from a directory and inserts
them into a transport ring as Earthworm messages.

The main advantage of this system over import/export is that files are
buffered in the directories used by sendfileII and file2ew. So if these
programs are not able to transmit thier input files, such as when the
recipient host is down, that data is held instead of being lost.

This file-based exchange system is NOT suitable for high data-rate exchanges
such as waveforms.

The programs sendfileII and getfileII are derived from the sendfile and
getfile programs contributed by Will Kohler at the Menlo Park campus of
USGS. The new programs use an enhanced protocol; the original programs could
lose files in certain circumstances. The new programs are NOT COMPATIBLE with
the original sendfile and getfile programs, nor with the getfile_ew program.
These programs are sometimes known as the "file flinger".

The ewfile progam can be configured to generate heartbeat files to send
through the system. If desired, the program makehbfile can be used instead to
generate heartbeat files. Makehbfile is also part of the sendfile/getfile
package from Will Kohler. The file2ew program can be configured to expect
heartbeat files and to send alarm messages on loss of heartbeats.

The three programs sendfileII, getfileII and makehbfile can be used
independently from earthworm. Their source files stand alone, needing none of
the Earthworm libraries. These three programs do not connect to Earthworm
transport, and thus can not be monitored directly by statusmgr.

The file2ew progam is a generic version of the family of strong motion file
converters (sm_file2ew); it has been part of Earthworm for some time. 

Note that ew2file can write  copies of its files to multiple directories, and
that getfileII can accept connections from multiple sendfileII's. So this
system offers considerable flexibility for complex data exchanges.
Pete Lombard, 12/20/2002

wave_probe:
Wave_probe is a new piece of diagnostic software for wave servers.  It is
mainly intended for use by developers.  Wave_probe constructs and sends
a trace request for a single station, logging to a debugging file everything
that occurs during this process.  This program is intended as a work in 
progress, as new errors are diagnosed and debugged, functionality can be
added as needed.  Wave_probe uses private versions of the ws_clientII    
librarys, so changes to ws_clientII would have to be replicated here also
John Patton, 02/06/2003

naqsserTG: New client to NaqsServer that takes transparent serial packets
containing tide gauge data and converts it into Earthworm messages and
write the data to a file. Written by Paul Whitmore, ATWC. 
LDD 2/14/2003

Latency Monitor:
This program looks at waveform messages dropped in an Earthworm Ring and 
logs latency and outages of the data. The graphical output shows a line
for each station for a set length of time.  Colors on the line represent 
the latency of the station over that time interval. The program was orginally 
written by Paul Whitmore at WC/ATWC and enhanced by John Patton at USGS, Golden.

FOR INTERACTIVE, ORACLE-BASED EARTHWORM

CONCIERGE:  
A system of programs that retrieves snippets from
wave_servers and stores them in an EW Database.  There are currently
three executables:  ora_trace_req, ora_trace_fetch, and unlocker.
Please see their web documentation for more info.

ora_trace_req:  A moduel that reads EW Trigger messages and converts
them to snippet requests which it inserts into the database.
Front half of concierge.  Replaces the front half of ora_trace_save.

ora_trace_fetch:  A module that reads snippet requests from an EWDB
and retrieves snippets to fill the requests.  The snippets are then
stored in the EWDB.   Back half of concierge.  Replaces the back half
of ora_trace_save.

unlocker:  Stand alone executable that releases old stale locks,
such as those that are generated when ora_trace_fetch is processing
requests and crashes or gets bonked on the head.
DK 2002/05/15

Jiggle: 
Jiggle was developed by Doug Given at USGS Pasadena for routine analysis 
of data collected  by TriNet in Southern California.
The Golden development team has incorporated Jiggle with the 
Earthworm DBMS.

gencatalog:
gencatalog allows the user to search the Earthworm database and generate 
a summary file of all events which meet user selectable criteria.

MODIFICATIONS/BUG FIXES TO EXISTING MODULES:

/libsrc/util/k2evt2ew: Added checksum and sanity checks so that reading
a bad .evt file will report an error, and a crash.

libsrc/util/k2evt2ew:  Modified the MAXTRACELTH constant in k2evt2ew.h,
so that a maxium of 800k datapoints per channel per EVT file are supported.
WARNING!!!!!:  This brings the K2InfoStruct memory footprint to a whopping
150MB!!!!  Any program that utilizes this library must be capable of 
allocating the structure.
Fixed a bug that allowed the library routines to write passed the end of
the K2InfoStruct data fields.  Main routine now truncates processing 
when the end of the output buffer has been reached and returns a truncation
warning.
DK 20030108

reaper: Had a hard-coded max of 1000 events to delete. Added a loop
to delete events in multiples of 1000. Alex 7/26/02

adsend: Modifications to run at digitizing rate up to 500 sps. Some few tweaks to irige.c.
Also tweaks to permit the user to set the actual number of channels to
be digitized (rather than all). Outstanding problem: irige.c likes it
best when a buffer contains one second's worth of data. Alex 7/17/02

shakemapfeed: Added new configuration file command "UseEventID" so the 
user can specify which eventid is written to the output files 
(1=binder's eventid, 2=DBMS eventid).  Changed logging so that both ids 
are written where applicable.  Changed so the log file is initialized 
before the configuration file is read so that configuration errors will 
now be written to the log file.  LDD 4/12/2002

sm_ew2ora:  Changed to issue a TYPE_ERROR msg if it cannot put SM data 
into the DBMS because the channel is not in the DBMS (previously, it 
only logged this info).  Changed to use tport_copyfrom instead of 
tport_getmsg. Moved logit_init such that configfile errors can be
logged and changed fprintf(stderr...) to logit("e"...) in the configuration
section.  LDD 5/1/2002
   Added 2 new Earthworm error codes to distinguish among the reasons
that SM data was not inserted in the DBMS.  Three codes now exist:
ERR_DBMSPUT (the call to ewdb_api_PutSMMessage failed)
ERR_UNKNOWNCHAN (channel info not in DBMS or has empty lat/lon)
ERR_CREATEEVENT (the call to ewdb_api_CreateEvent failed) LDD 3/13/2003

k2ew (tcp version only):  Changed program so that heartbeats are sent to
statmgr while k2ew is attempting to make a socket connection to the K2.
Changed k2ew version number to 2.30.  WMK 5/6/2002

scream2ew:  Added new config command "IPNumber" so that the user can 
specify the IP number on which SCREAM transmits data.  JMP 05/08/2002
        Rewrite by Guralp to accept data via TCP as well as UDP. AB 03/05/03
        New version from Guralp to fix memory leak. AB 03/27/03

findwave:  Modified findwave so that it can produce output compatible with
waveserverV .tnk file (scns to save) in addition to it's existing output. 
Usage: findwave     
Where  is the ring to attach to,
       is the desired waveserverV index size,
       is the number of days to save data in a waveserverV tank,
       is the output file name, and
       = w for waveserverV output using the above parameters, or
       = d for debug output, providing: Station name, Component,
      Network, Maximum Message Length, Minimum Message Length, Message Arrival
      Rate, Total number of Messages, and estimated Megabytes per day.
JMP 05/14/2002 

wave_serverV:  (serve_trace.c)
Fixed a bug in the fill logic, that caused one to few samples to be
filled.  Bug was noticed by Carol Bryan.
DK 10/11/2002

binder_ew: Changed the stack weighting scheme to include not only the pick
quality, but also the installation id that produced the pick. For example,
this allows a user to weight a quality 2 pick from one installation differently
than a quality 2 pick from a different installation.  Added a new config file
command, grid_wt_instid, to set the weighting.  The original grid_wt
command will result in all picks being weighted by their quality alone.
LDD 5/23/2002 

export_scn_remap: Removed this module. Its functionality has been merged
with export_scn.  LDD 10/29/2002

export_scn: Added a new optional command, Send_scn_remap, that allows the
user to change the SCN of outgoing trace data on the fly.  Also added
TYPE_TRACE_COMP_UA as a message type that scnfilter can work on. Moved the
MaxLatency check to a section of code after the SCN check for efficiency.
Made other cosmetic changes to the code.  Merged the priority features
of scnprifilter.c into scnfilter.c to eliminate lots of duplicate code.
LDD 6/11/2002
  Modified to use binary search when matching SCN of message to the 
requested channel list. Binary search is only used if the requested
channel list does not contain any wildcards.  If wildcards are present,
export_scn uses the same linear search for SCN matching as it used to.
The binary search makes exports with long requested channel lists much
more efficient.  LDD 10/29/2002

compress_UA,
decompress_UA: Added optional config command, UseOriginalLogo, to allow 
user to apply the installation id & module id of the original compressed
msg to the outgoing decompressed message. This will make it possible for
one instance of compress_UA or decompress_UA to work on data from 
multiple sources without losing the source information. The default 
behavior is that the (de)compress_UA installation id & module id will
be applied to all outgoing data. LDD 6/19/2002

decompress_UA: Fixed a bug in brtt_genuncompress() which caused an
infinite loop. It entered a while loop controlled by the size variable,
but the value of size never changed inside the loop:
BUG:  *size *= (int) 1.2;  (size never changes! same as *size *= 1)
FIX:  *size  = (int)(1.2 * *size);
This loop is to realloc the buffer used to decompress the data.
LDD 8/13/2002

swap.c:  Added fix by P. Friberg, to a bug in the code that checksums
the header in WaveMsgMakeLocal before byte-aligning it, resulting in
a bus-error core dump under gcc/solaris when double arithmetic is
attempted on a non-aligned variable.  Fix was run-tested on Solaris
by Friberg, compile tested on NT by DK.
DK 2002/06/11

Fixed the sanity check in WaveMsgMakeLocal() that ensures a trace_buf
header is reasonably sane before attempting to byteswap the data.
DK 2002/06/18

QUICK REVIEW:   Fixed creation of SAC files for review so that 
horizontal components which have gaps in data are not written out.
This is necessary so that localmag under review does not attempt to 
use gappy data.

statmgr: Changed to allow an optional command, pagegroup, in each
descriptor file.  If the descriptor file contains a pagegroup 
command, it overrides the pagegroup in statmgr's config file.
Otherwise, the pages will be sent to the pagegroup in statmgr's
config file.  LDD 2002/07/09

heli_ewII.h: Changed lengths of Site, Comp, and Net fields of Butler
struct to allow for NULL byte in standard-length EW SCN names.
5-letter Sites were being mis-interpreted due to lack of space
for the NULL.  Still lacks string-length checks all over the
place.  LDD 2002/07/16

hyp2000: Newest version of hyp2000 code was copied into Earthworm from
Fred Klein's directories on swave.wr.usgs.gov.  LDD 2002/09/20

decimate: Modified to be able to accept up to 10 GetWavesFrom commands.
Fixed bug that was causing core dump on exit if input and output
rings were the same ring. LDD 2002/10/25
 
naqs2ew: Added code to handle extended seismic data headers in the
compressed data packet.  These headers are used by the new Trident
digitizer.  Previous versions of naqs2ew did not handle compressed
data packets from Tridents properly (decompressed packets were OK).  
Now compressed data packets from ALL Nanometrics digitizers are
handled properly. LDD 2002/10/25

naqssoh: Added support for decoding and logging Libra time quality
SOH information.  LDD 2002/11/08

file2ew,sm_*2ew: Fixed faulty logic for handling files which cannot
be opened.  Previously, even though the file was not open, we tried
to read it.  Now, if a file cannot be opened an error message is
generated and an attempt is made to move the file to the trouble
directory.  If the file cannot be moved, the program exits. If the
file can be moved, the program continues operating. LDD 2002/12/05

file2ew:
  An optional installation id argument was added to the SuffixType
command to allow file2ew to assign "foreign" installation ids to
messages it places in the local ring.  If the installation id is
ommitted, file2ew uses its own installation id as before. LDD 2002/12/05

eqfilter:
Added a new test, nphtotalTest, which checks the total number of
phases with weight>0.0.  The original nphTest still exists, and
checks the number of phases with weight>0.1. Changed wording of 
some log messages for clarity. Changed to reject event after the 
first test it fails instead of continuing with other tests.
LDD 2002/12/10

coaxtoring:
I found a case where the coaxtoring module if killed at startup, would
not get restarted by statmgr since it did not beat its heart till after
HeartbeatInt seconds. To remedy this, I simply had the heartbeat thread
beat the instant it was forked and this seems to have solved the issue.
Paul Friberg 2002/12/27

Nanometrics API (nmx_api):
Added functions to interpret Nanometrics "transparent serial packets".
New functions were first used by Paul Whitmore's naqsserTG module for
handling tide gauge data.  LDD 2003/2/14

carlsubtrig,evansassoc:
Both of these modules had a bug in writing one of the comment lines in
the TYPE_TRIGLIST2K message and their log files.  The comment line was
changed from "Sta/Net/Cmp...." to "Sta/Cmp/Net...." to match the order
in which those fields are actually written to the message.  The parsing
routine (libsrc/util/parse_trig.c) totally ignores that comment line, so the
change should have no effect on consumers of the message.  LDD 2003/02/28

pickew:
In GetStaList() (in stalist.c), the station list
file is read in. There are two counts made of this file. The first count looks
for non-comment lines, and then allocates are array for that many STATION
structures. Then GetStaList reads the file again, loading the station data
into the array. But this time, only lines with the pickflag set are loaded
into the array. After the file reading is completed, then the return parameter
Nsta is set to the number of stations read in:
    *Nsta = nsta;
This is not right: it should be:
    *Nsta = i;
nsta is the number of non-blank lines, NOT the number of stations to be
picked. The result is that the Sta array contains a number of empty STATION
structures which now get searched each time a trace packet comes into
pick_ew. The result can also be seen in the pick_ew log: there are a number of
lines containing only zeros before the real station lines. An additional
effect is that if the last station line in the station list file has its pick
flag set to zero, it will be picked anyway.
Problem fixed by PNL, 3/24/2003

gmew:
Added parameter 'snrThresh T'.
Minimum accepted signal-to-noise threshold....traces are rejected unless
this threshold is passed.
Default: 3.0
Added by DH, 9/25/2002


Wave_serverV:
Fixed bug where Wave_serverV would not work probably on multi-home 
systems under Windows 2000.
Added by DH, 4/15/2003


CHANGES TO CONFIGURATION FILES and DESCRIPTOR FILES:
****************************************************

shakemapfeed.d:
Added new required command, UseEventID, to allow the user to choose which
eventid will be written to the output files. Valid arguments are 
1=binder's eventid, or 2=DBMS eventid.  LDD 4/12/2002 

scream2ew.d:
Added new required command, IPNumber, so that the user can 
specify the IP number on which SCREAM transmits data.  For a SCREAM
directly connected, use 127.0.0.1 (local host).  For a remote
SCREAM, use the IP number associated with it.  JMP 05/08/2002

binder_ew.d:
Added a new optional command, grid_wt_instid, so that the user can set
stackin weights based on pick weight and installation id.  The original
command, grid_wt, still exists and allows stacking weights based on
pick quality alone.  LDD 5/23/2002 

export_scn.d
Added a new optional command, Send_scn_remap, that allows a user to
change the SCN (any or all of the three fields) on outgoing trace
data (either TYPE_TRACEBUF or TYPE_TRACE_COMP_UA). LDD 6/11/2002

eqfilter.d
Added a new optional command, nphtotalTest, which allows a user to
set a lower limit on the total number of phases with weight > 0.0.
The original command, nphTest, still exists and sets the lower 

compress_UA.d,
decompress_UA.d
Added optional config command, UseOriginalLogo, to allow user to
apply the installation id & module id of the original compressed
msg to the outgoing decompressed message (if argument is non-zero). 
If UseOriginalLogo is zero, then all outgoing messages will be
labeled with decompress_UA's installationid & moduleid.  LDD 6/19/2002

file2ew.d
Added optional argument to SuffixType command to allow the user
to assign a "foreign" Installationid to messages based on the
suffix of the filename.  If this argument is ommitted, file2ew
uses its own installation id (same as previous behavior). LDD 12/5/2002

Any .desc file
Any .desc file can now optionally contain a pagegroup command.
If it exists, it will override the pagegroup listed in statmgr's
configuration file.  LDD 7/9/2002

k2ew_tcp.d
The k2ew_tcp process takes a while to cleanly exit when the program
is told to terminate by startstop. If the KillDelay parameter is not
set to something larger than 10-15 seconds, the k2ew_tcp process will
not die cleanly in the time expected and will never get restarted by
startstop resulting in a zombie process. I added a note to this effect
to the k2ew_tcp.d file reminding others of this situation.
Paul Friberg 12/27/2002

sm_ew2ora.desc
Added three new error codes to distinguish among the reasons the
insertion of SM data into the DBMS failed.  LDD 3/13/2003


KNOWN BUGS:
***********
k2ew: 
k2ew uses the k2hdr.rwParms.misc.channel_bitmap parameter to decide
which channels it will see as streams from the K2.  This is actually the
parameter which the K2 uses to decide which channels to record in an event
file (see K2's  command).  The K2's  is the parameter
that shows which channels the K2 is streaming out.  This is the parameter
that k2ew should be using to decide what data it will see.  The big problem
is that none of the header files from Kinemetrics (nkwhdrs.h) seem to 
show this parameter anywhere. This issue is only a problem for those folks
who want to record more channels on the K2 than they want to stream continuously.
Terry Dye (Univ of Utah) discovered this problem when trying to stream only
3 channels of a 12 channel K2.  LDD 4/11/2002 

wave_serverV:
it occasionally sends the following error to statmgr:
   UTC_Thu Sep 06 03:30:14 2001  WSV1/wave_serverV_nano ReadBlockData
   failed for tank [z:\nano57.tnk], with offset[999908] and record
   size[64]! errno[0] Mail sent.
The nominal tank size is 1 megabyte, and the actual tank size is 999908.
It looks like waveserver is trying to read off the end of the tank.
WMK 9/6/01

wave_serverV:
appears not to reply to requests for a single sample of data. I noticed 
when testing wave_viewer, that if the start time and end time of a request were 
equal (in which case there should be one sample of data) then wave_serverV did 
not reply to the request (ASCII request) at all. No Data, No Flags, No Reply, 
No Nothing.  It needs to issue a reply to every request.
DavidK 09/25/01

Automatic restarts of adsend (using the "restartMe" line in the descriptor
file) can cause an NT system to hang. Therefore, you should never
use the autorestart feature with adsend, but you should bring down
the entire Earthworm system if adsend needs to be restarted.
LDD 5/31/2000 Comments added to adsend.desc, but leave this warning here!

libsrc/utils/site.c: The strings used for station, channel and network are
required to be fixed length with trailing spaces added to short names. If
the strings given to site_index do not have these trailing blanks, SCN names
will not match. This is not documented anywhere.  PNL 10/15/00

socket_ew: (libsrc/util/socket_ew_common.c libsrc/solaris/socket_ew.c
            libsrc/winnt/socket_ew.c include/socket_ew.h)
Fixed a bug in the connect_ew function().
When run in non-blocking mode (clients connecting to
a server - using a timeout value), there was a bug in
the connection code(discovered on Solaris) that caused
the function to return a timeout-error when there was
any kind of error during connection.
The bug was discovered when connecting to a non-existent socket.
When trying to connect to a non-existent wave_server on a machine,
the underlying socket library was returning a Connection-Refused error,
but the socket_ew library was passing back a timeout error.
-
The change only applies when a socket-error occurs while the function is
waiting for the connect to happen.  The instance where you will most-likely
see a difference, is when you try connecting to a non-existent socket.
Previously the function would return TIMEOUT, now it will return
connection REFUSED.
-
Added a new function: socketSetError_ew(),
and defined a new socket_ew return code: CONNREFUSED_EW.
DK 2003/02/04

sm_ew2ora:
There is a bug in sm_ew2ora that involves having multipe time intervals for
components and channels.  If a strong motion message containing information
for a channel that the DB has never seen before is loaded into the DB, and
then later another message for the same channel with an earlier timestamp
is loaded, the load of the second message will fail, due to problems with
overlapping time intervals, and the call that sm_ew2ora uses to create
those time intervals.  This problem only affects stations that were
not previously loaded via one of the station loader programs stalist*2ora,
and only when receiving SM data that is timestamped with a time that is
prior to the original time for that channel.  The bug lies in the logic
of ewdb_api_PutSMMessage(), and not in the underlying code.
Davidk 05/25/01

A change was made to ewdb_api_PutSMMessage() that dramatically affects
sm_ew2ora.  Please see the note about that function.  Davidk 2001/07/26 

ewdb_api_CreateWaveform()  (ewdb_internal_CreateSnippet.c 
                            ewdb_internal_CreateWaveformDesc.c)
Added a call to release the cursors used by the internal functions, when they
fail.  Fixes a bug which resulted in a DB cursor leak when a call to stuff
a snippet into the DB failed.
DK 2003/02/04


KNOWS DEFICIENCIES:
*******************

ringtocoax:
In Windows NT, the time resolution of sleep_ew() is about 16 msec (one clock
tick).  On Solaris, the resolution is about 10 msec.  This is a problem for 
ringtocoax, since packet delays need to be set to a few milliseconds.

statmgr: A space is needed between "tsec:" and the value. 
If it isn't there, things fail. Artifcat of the kom routines. (Alex)

threads functions: The KillThread function on WindowsNT and Solaris
terminate the thread without ensuring that no mutexes are held. If a thread
holds a mutex when it dies, no other thread can get that mutex. PNL 1/12/2000

carlsubtrig:
The system time must be set to GMT and ew_nt.cmd must have 
TZ=GMT for carlsubtrig to work.  Comments in ew_nt.cmd done 5/25/00. Barbara
        
localmag:
needs GMT set on the system

ew2seisvole:
on NT, exits with horrible crash when system is stopped.

NUMBER OF RINGS LIMITED ON SOLARIS:
Under Solaris 2.6 (and probably other versions as well), the maximum number 
of shared memory segments is six. This means that on an out-of-the-box machine
you can only configure six rings. If you try to configure more than that, you
will see a cryptic message from tport_create about too many open files.  The
fix to this problem is to add the following lines to the /etc/system
file, and then reboot the system.

 set shmsys:shminfo_shmmax = 4294967295
 set shmsys:shminfo_shmmin = 1
 set shmsys:shminfo_shmmni = 100
 set shmsys:shminfo_shmseg = 20
 set semsys:seminfo_semmns = 200
 set semsys:seminfo_semmni = 70

This allows for 20 rings.

     Lucky Vidmar (7/6/2000)


startstop_solaris: 
There MAY be a problem with the signal that 
startstop sends to modules during the shutdown sequence. The shutdown 
sequence is started (after typing "quit" to startstop or running "pau")
by startstop placing a terminate message on all transport rings. Modules
should see this message and start their own shutdown. After a configurable
delay, startstop checks to see that all modules have exitted. Any that are 
still running are sent a signal to terminate them. Currently that signal
is SIG_TERM. But since wave_serverV has a handler for SIG_TERM, wave_serverV
sees that as essentially the same as a terminate message. So if wave_serverV
is having problems completing its shutdown, SIG_TERM won't do anything. The
result is that startstop may give up and exit, leaving wave_serverV running.
If that happens, the operator will have to terminate wave_serverV by doing
"kill -9 ". That may leave shared memory and semaphores
stranded in the kernel: run the command "ipcs -a" to see. If necessary,
the stranded shared memory and semaphores may be cleaned up with the
ipcrc command; must be run as root; see the man page.
This problem only exists on Solaris/Unix, not on WindowsNT.
PNL, 10/4/2000

libsrc/utils/kom.c:  fix comment in k_open()

The comment above k_open() says that only one file can
be open at a time. Yet the Kbuf array has slots for MAXBUF (currently 4) open
files. Does this work, or is the comment to be taken at it's word?
PNL 10/15/00

libsrc/utils/logit.c: logit_init() requires a module_id number, which it uses
to construct the log file name. This is not helpful, since the module_id
number is not meaningful to people. Worse, it requires that the config file be
read and earthworm.d lookups be completed before logit calls can be made. Thus
errors in the config file can only be reported to stderr or stdout instead of
being saved in a file.  PNL 11/29/00

libsrc/util/k2evt2ew.c: This library supports a maximum EVT data size
of 800000 samples per channel per EVT file.  This value is hardcoded
as MAXTRACELTH in include/k2evt2ew.h.  k2evt2ew() will return a warning
if the EVT file exceeds this size, and process as much as the EVT file
as the hardcoded limit allows.
DK 2003/01/18


TRACEBUF messages.
The definition of `endtime' of the TRACEBUF message is not documented.
Some programmers are taking it as the "expected start time of the next
TRACEBUF packet (if the sample interval is uniform.)" The more accepted
practice is that `endtime' is the time of the last sample of the current
TRACEBUF packet; that is, one sample interval less than the expected
start time of the next TRACEBUF messsage. Using this last definition, if a
TRACEBUF packet has exactly one sample, then its starttime and endtime are
the identical. Clearly this distinction needs to be documented. The file
waveform_format (in the /home/earthworm/DOC directory) gives no specifics 
about start or end times.  PNL 1/24/01
 

The URL of this page is [http://gldbrick.cr.usgs.gov/ew-doc/RELEASE/release_notes_v6.2.html]
Contact: bogaert@usgs.gov