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The cat is pointless so that can go. Identifier is not in your sample input so let's assume you meant blabla. Your request to delete the users last name seems completely unrelated to your example command so let's just change that

grep blabla file.log | perl -pe 's/ [^ ;]+;/;/g' > newfile.log

If that does not give you what you want you should rewrite your question so that it is clear.

The cat is pointless so that can go. Identifier is not in your sample input so let's assume you meant blabla. Your request to delete the users last name seems completely unrelated to your example command so let's just change that

grep blabla file.log | perl -pe 's/ [^ ;]+;//g' > newfile.log

If that does not give you what you want you should rewrite your question so that it is clear.

The cat is pointless so that can go. Identifier is not in your sample input so let's assume you meant blabla. Your request to delete the users last name seems completely unrelated to your example command so let's just change that

grep blabla file.log | perl -pe 's/ [^ ;]+;/;/g' > newfile.log

If that does not give you what you want you should rewrite your question so that it is clear.

1
source | link

The cat is pointless so that can go. Identifier is not in your sample input so let's assume you meant blabla. Your request to delete the users last name seems completely unrelated to your example command so let's just change that

grep blabla file.log | perl -pe 's/ [^ ;]+;//g' > newfile.log

If that does not give you what you want you should rewrite your question so that it is clear.