RSyslog Documentation



field(str, delim, matchnbr)

Returns a field-based substring. str is the string to search, delim is the delimiter and matchnbr is the match to search for (the first match starts at 1). This works similar as the field based property-replacer option. Versions prior to 7.3.7 only support a single character as delimiter character. Starting with version 7.3.7, a full string can be used as delimiter. If a single character is being used as delimiter, delim is the numerical ascii value of the field delimiter character (so that non-printable characters can by specified). If a string is used as delimiter, a multi-character string (e.g. “#011”) is to be specified.


When a single character is specified as string field($msg, ",", 3) a string-based extraction is done, which is more performance intensive than the equivalent single-character field($msg, 44 ,3) extraction.


With ascii value of the field delimiter

Following example returns the third field delimited by space. In this example $msg will be “field1 field2 field3 field4”.

set $!usr!field = field($msg, 32, 3);



With a string as the field delimiter

This example returns the second field delimited by “#011”. In this example $msg will be “field1#011field2#011field3#011field4”.

set $!usr!field = field($msg, "#011", 2); -- the second field, delimited by "#011"



See also

Help with configuring/using Rsyslog:

  • Mailing list - best route for general questions
  • GitHub: rsyslog source project - detailed questions, reporting issues that are believed to be bugs with Rsyslog
  • Stack Exchange (View, Ask) - experimental support from rsyslog community

See also

Contributing to Rsyslog:

Copyright 2008-2020 Rainer Gerhards (Großrinderfeld), and Others.

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