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-rw-r--r-- | doc/rsyslog_conf_nomatch.html | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/doc/rsyslog_conf_nomatch.html b/doc/rsyslog_conf_nomatch.html index 5c4f3f90..5f25f3e4 100644 --- a/doc/rsyslog_conf_nomatch.html +++ b/doc/rsyslog_conf_nomatch.html @@ -8,9 +8,11 @@ of the <a href="property_replacer.html">property replacer</a>.</p> shall return if a regular expression did not find the search string.</b>. Traditionally, the string "**NO MATCH**" was returned, but many people complained this was almost never useful. Still, this mode is support as "<b>DFLT</b>" for legacy configurations. -<p>Two additional and potentially useful modes exist: in one (<b>BLANK</b>) a blank string +<p>Three additional and potentially useful modes exist: in one (<b>BLANK</b>) a blank string is returned. This is probably useful for inserting values into databases where no -value shall be inserted if the expression could not be found. A use case may be +value shall be inserted if the expression could not be found. +<p>A similar mode is "<b>ZERO</b>" where the string "0" is returned. This is suitable +for numerical values. A use case may be that you record a traffic log based on firewall rules and the "bytes transmitted" counter is extracted via a regular expression. If no "bytes transmitted" counter is available in the current message, it is probably a good idea to return an empty string, which the @@ -23,6 +25,15 @@ it shall be logged. checker and generator</a> to see these options in action</b>. With that online tool, you can craft regular expressions based on samples and try out the different modes. +<h2>Summary of nomatch Modes</h2> +<table border="1" cellspacing="0"> +<tr><td><b>Mode</b></td><td><b>Returned</b></td></tr> +<tr><td>DFLT</td><td>"**NO MATCH**"</td></tr> +<tr><td>BLANK</td><td>"" (empty string)</td></tr> +<tr><td>ZERO</td><td>"0"</td></tr> +<tr><td>FIELD</td><td>full content of original field</td></tr> +<tr><td> </td><td><a href="http://www.rsyslog.com/tool-regex">Interactive Tool</a></td></tr> +</table> <p>[<a href="manual.html">manual index</a>] [<a href="rsyslog_conf.html">rsyslog.conf</a>] [<a href="http://www.rsyslog.com/">rsyslog site</a>]</p> |