To tail a file means to keep it open and watch new lines that are appended to it by some other program.

tail is a classic Unix text processing utility which displays the last few lines of a file. It introduced “follow mode”, where the file is kept open and the utility prints new lines as they appear.

Use this tag when tailing files, regardless of whether you are using the tail utility itself. A question about using tail which isn't about follow mode should probably use the tag. Not to be confused with the Tails operating system . For monitoring of changes to files in general, see .

Common tailing utilities

Further reading

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