#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?m)^(\d+/\d+/\d+ \d+:\d+:\d+)\s+\S+\s+\S+\s+(.+), client"
Local $sString = "2019/03/15 14:22:59 [error] 14064#0: <error I need to find>, client: XXX.XXX.XXX.XXX, server: example.com, request: "POST /hello", host: "example.com"" & @CRLF & _
"2019/03/15 14:22:59 [error] 14064#0: <error I need to find>, client: XXX.XXX.XXX.XXX, server: example.com, request: "POST /hello", host: "example.com"" & @CRLF & _
"2019/03/15 14:22:59 [error] 14064#0: <error I need to find>, client: XXX.XXX.XXX.XXX, server: example.com, request: "POST /hello", host: "example.com"2019/03/15 14:22:59"
Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH)
Local $aFullArray[0]
For $i = 0 To UBound($aArray) -1
_ArrayConcatenate($aFullArray, $aArray[$i])
Next
$aArray = $aFullArray
; Present the entire match result
_ArrayDisplay($aArray, "Result")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm