dgsh-monitor.1

.TH DGSH-MONITOR 1 "11 December 2016"
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.SH NAME
dgsh-monitor \- monitor data on a pipe
.SH SYNOPSIS
\fBdgsh-monitor\fP
.SH DESCRIPTION
\fIdgsh-monitor\fP is a filter that reads lines from its standard input
and for each line writes a JSON record containing
the absolute timestamp (\fCatime\fP),
the relative timestamp (\fCrtime\fP),
the number of lines read (\fCnlines\fP),
the number of bytes read (\fCnbytes\fP),
and the actual data (\fCdata\fP).
The values printed are those that were in effect before the line's
first character was read (i.e. the number of bytes and lines starts at 0).
The timestamps are printed as a decimal number of seconds
(since epoch, January 1 1970, for the absolute one)
with microsecond precision.
.PP
The command can be used in conjunction with \fIdgsh-writeval\fP
for providing pipeline monitoring ports as a debugging aid.

.SH "SEE ALSO"
\fIdgsh\fP(1),
\fIdgsh-writeval\fP(1)

.SH BUGS
When providing data regarding a single record,
such as that written to a store,
it can be confusing to see all the numerical values as zero.

.SH AUTHOR
Diomidis Spinellis \(em <http://www.spinellis.gr>