uutils/coreutils

tail --follow=name accepts symlink replacements

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#10328 opened on Jan 18, 2026

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Description

Component

tail

Description

When using --follow=name, uutils tail accepts a file that has been replaced with a symlink and continues tailing the symlink target. GNU tail refuses to follow a path that becomes a symlink, printing "has been replaced with an untailable symbolic link".

Test / Reproduction Steps

cd /tmp && rm -rf tail_test && mkdir tail_test && cd tail_test
echo "original" > testfile

# GNU tail
timeout 2 tail --follow=name testfile &
sleep 0.3
rm testfile && ln -s /etc/passwd testfile
sleep 0.3
# Output: "has been replaced with an untailable symbolic link"

# uutils tail
rm -f testfile && echo "original" > testfile
timeout 2 tail --follow=name testfile &
sleep 0.3
rm testfile && ln -s /etc/passwd testfile
sleep 0.3
# Output: "'testfile' has appeared;  following new file" + contents of /etc/passwd

Contributor guide

Tech stack
rust
Domain
cli
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
basic Rustunderstanding of Unix symbolic links
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70
Research direction
Examine the `tail` command source code, likely in `src/uu/tail/src/tail.rs`. Look for the logic that handles ` follow=name` and file replacement. The fix should check if the new file at the path is a symbolic link after replacement and emit an error message similar to GNU's. Consider using `std::fs::symlink metadata` to detect symlinks without following them. Reference the GNU coreutils source for exact behavior.