regex101: PCRE (Legacy) Match Workspace

Initiated logon requestthe literal text Initiated logon request (case sensitive)

Group 1((?!Received logon)[\s\S])*

*repeats the group contents below any number of times:

Negative Lookahead(?!Received logon)

Received logonthe literal text Received logon (case sensitive)

Character Class[\s\S]

\sany whitespace character

\Sany non-whitespace character

Received logonthe literal text Received logon (case sensitive)

Global pattern flags

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

g modifier: global. Finds all matches instead of stopping after the first

Search reference

Regular Expression

Initiated logon request((?!Received logon)[\s\S])*Received logon

Test String
New

<20170503-18:19:09, FIXT.1.1:BANZAI->EXEC, event> (Initiated logon request)
  <20170503-18:19:09, FIX.4.4:BANZAI->EXEC, incoming> (8=FIX.4.4☺9=67☺35=A☺
  34=177☺49=EXEC☺52=20170503-18:19:09.298☺56=BANZAI☺98=0☺108=30☺10=092☺)
  <20170503-18:19:09, FIX.4.4:BANZAI->EXEC, event> 
  (Received logon) fdsfhffghgfhgjgf  177☺49=EXEC☺52=20170503-18:19:09.298☺
  56=BANZAI☺98 (Received logon) more stuff after this....

Regular Expressions 101

Regular Expression

Test String
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Substitution
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Regular Expression

Test StringNew

SubstitutionProcessing...

Test String
New

Substitution
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