Table of Contents

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This component writes records passing through the <flow> into <file> in text format.

Works only when variable ‘EVL_WATCHER’ is set to ‘1’, otherwise does nothing. One can use it for debugging data in ‘DEV’ or ‘TEST’ environment, but it would be switched off in ‘PROD’.

EVD is EVL data definition file, for details see evl-evd(5).


  <flow> <file> (<evd>|-d <inline_evd>) [-x|--text-input]

evl watcher
  ( --help | --usage | --version )


-d, --output-definition=<inline_evd>

either this option or the file <evd_out> must be presented. Example: ‘-d 'user_sum long'

-x, --text-input

suppose the input as text, not binary

Standard options:


print this help and exit


print short usage information and exit


print version and exit


  1. In EVL job (‘evs’ file):
    Sort     FLOW_01 FLOW_02 some.evd --key='id'
    Watcher  FLOW_02 sorted.csv some.evd