uutils/coreutils

uu timeout is less precise than GNU timeout

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#11615 opened on Apr 3, 2026

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 (7 comments) (3 reactions) (0 assignees)Rust (23,246 stars) (1,852 forks)batch import
U - timeoutgood first issuereported-canonical-2

Description

uu timeout sleeps for 100ms intervals at https://github.com/uutils/coreutils/blob/2319a99057d11b0c9744c885df84806eea019166/src/uucore/src/lib/features/process.rs#L163 instead of using timer_create or setitimer, which are more precise.

timeout (GNU coreutils) 9.7
Packaged by Debian (9.7-3)                                                                                                                                                                                            Copyright (C) 2025 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.                                                                                                                                                    There is NO WARRANTY, to the extent permitted by law.

Written by Padraig Brady.                                                                                                                                                                                             root@b082d601e194:/tmp# time timeout 0.01 sleep 1
real    0m0.014s
user    0m0.000s
sys     0m0.004s

root@03081849be59:/tmp# timeout --version
timeout (uutils coreutils) 0.6.0
root@03081849be59:/tmp# time timeout 0.01 sleep 1
                                                                                                                                                                                                                      real    0m0.117s
user    0m0.002s
sys     0m0.014s                                                                                                                                                                                                      ```

Contributor guide

Tech stack
rust
Domain
cliperformance
Issue type
performance
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.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Rust programmingUnix system programmingfamiliarity with uutils codebaseknowledge of timer create/setitimer
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40
Research direction
Investigate replacing the 100ms interval sleep at src/uucore/src/lib/features/process.rs:163 with a more precise timer using timer create or setitimer. Review the linked source code and understand how timeout currently works. Consider consulting comments in the issue for any additional context. Ensure the implementation remains cross platform if needed.