Splunk Search

Text function replace and "\"

osakachan
Communicator

Hello folks,

I am experiencing problems to use replace to change a field value like "qwerty\foo" to "qwerty\foo".

I am testing it with this query

    | makeresults
    | eval user="qwerty\foo"
    | eval ruser=replace(user,"\\","\\")

In this case I have this error
Error in 'eval' command: Regex: \ at end of pattern

The same for:
| eval ruser=replace(user,"\","\\")

Using | eval ruser=replace(user,"\{1}","anything") , It does not show an error but nothing changes. The same for + or *.

Using | eval ruser=replace(user,"\\","a") shows the next error, and of course If use another " nothing will change.
Unbalanced quotes.

With | eval ruser=replace(user,"(.)\(.)","\1\\\2") no error but nothing changes and | eval ruser=replace(user,"(.)\(.)","\1\\\2") shows the next error:
Error in 'eval' command: Regex: unmatched closing parenthesis

Just in case tested | eval ruser=replace(user,"/\","/\/\") , error
Error in 'eval' command: The expression is malformed. An unexpected character is reached at '\/\")'.

The only thing worked for reading \ was this regex:
| eval ruser=replace(user,"(.)\(.)","\1(\)(\)\2")

But the output I was unable to output a double \

Because I am unable to rex it a temporary solution was this.

| makeresults
| eval user="qwerty\foo"
| eval tuser=replace(user,"(.*)\\\(.*)","\1?\2")
| rex field=tuser "(?<u1>[^\?]+)\?(?<u2>[^\?]+)"
| eval ruser=u1+"\\\\"+u2

¿Someone know the way to use replace in this case to make things easy? Thanks 🙂

0 Karma
1 Solution

justinatpnnl
Communicator

Try this:

| makeresults 
| eval user="qwerty\foo" 
| eval ruser=replace(user,"\\\\","\\\\\\\\")

In SPL, the escape has to be escaped so everything doubles. If you want to find a backlash, you would normally look for \. But in SPL you have to escape your escape: \ and then escape the backslash you are trying to find with another \.

https://docs.splunk.com/Documentation/Splunk/7.3.0/Search/SPLandregularexpressions

View solution in original post

justinatpnnl
Communicator

Try this:

| makeresults 
| eval user="qwerty\foo" 
| eval ruser=replace(user,"\\\\","\\\\\\\\")

In SPL, the escape has to be escaped so everything doubles. If you want to find a backlash, you would normally look for \. But in SPL you have to escape your escape: \ and then escape the backslash you are trying to find with another \.

https://docs.splunk.com/Documentation/Splunk/7.3.0/Search/SPLandregularexpressions

osakachan
Communicator

So many banelings!!err.. I mean, \\\\\ 🙂

Works as intended, I did not understand the double scape so I've used 3 \ instead of 4 \ 🙂

Thanks for the answer.

0 Karma
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