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Rev

I found two caveats: if the target file is empty it copies nothing (instead it should copy all the lines). Then I tried to put inside a valid line, but it copied all of them, not only the next ones.

Mark
– Mark

2020-11-30 12:51:50 +00:00
Commented Nov 30, 2020 at 12:51
@Mark well yes. You wanted to specifically avoid duplicates. There's no point in running this if you don't have duplicates. If the file is empty, just run grep myentry /var/log/syslog. I don't understand the second point. Please add an example to your question. I used the data you gave and it worked as expected.

terdon
– terdon ♦

2020-11-30 13:10:50 +00:00
Commented Nov 30, 2020 at 13:10

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