Public bug reported:
Apparent regression in the `watch` utility (procps package) where using
the `--differences=permanent` flag marks completely identical output
text as "changed," highlighting the entire terminal block on the second
iteration onwards.
Steps to Reproduce:
1. Open a fresh terminal window.
2. Execute the following command:
watch --differences=permanent echo foobar
3. Wait for the second iteration (by default, 2 seconds).
Expected Result:
The terminal should display "foobar" cleanly. Since the output of `echo foobar`
does not change between iterations, no text should be highlighted.
Actual Result:
On the first iteration, "foobar" is unhighlighted. On the second iteration, the
entire word "foobar" becomes permanently highlighted in reverse video, despite
the string matching the previous iteration exactly.
Additional Context:
- OS: Ubuntu 24.04 LTS
- Package: procps
- This mirrors the upstream bug filed in procps-ng/procps Issue #391 ("watch
--differences=permanent highlights everything as changed").
ProblemType: Bug
DistroRelease: Ubuntu 24.04
Package: procps 2:4.0.4-4ubuntu3.2
ProcVersionSignature: Ubuntu 6.8.0-137.137-generic 6.8.12
Uname: Linux 6.8.0-137-generic x86_64
ApportVersion: 2.28.3-0ubuntu0.1
Architecture: amd64
CasperMD5CheckResult: pass
Date: Fri Aug 14 22:02:41 2026
InstallationDate: Installed on 2026-06-25 (50 days ago)
InstallationMedia: Ubuntu-Server 24.04.4 LTS "Noble Numbat" - Release amd64
(20260210)
ProcEnviron:
LANG=en_US.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=xterm-256color
XDG_RUNTIME_DIR=<set>
SourcePackage: procps
UpgradeStatus: No upgrade log present (probably fresh install)
** Affects: procps (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug noble
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2163557
Title:
`watch --differences=permanent` erroneously highlights all static text
on subsequent iterations
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/procps/+bug/2163557/+subscriptions
--
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
