uutils/findutils

`-printf` panics on an invalid-UTF-8 format string (exit 101)

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#816 opened on Aug 7, 2026

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good first issue

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Description

A -printf format string that is not valid UTF-8 panics during argument collection, before the format parser is ever reached.

$ find d -printf $'%\xff|\n'
thread 'main' panicked at ...: called `Result::unwrap()` on an `Err` value
$ echo $?
101

The panic is in std::env::args, which panics on non-UTF-8 arguments. Collecting via std::env::args_os and handling the invalid-UTF-8 case explicitly would let this produce a normal error (or match GNU, which accepts arbitrary bytes in the format string and passes them through).

Contributor guide

Research direction
Investigate how command line arguments are collected using std::env::args and consider switching to std::env::args os with explicit handling of non UTF 8 arguments to avoid panics.
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.
2
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
RustGit
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70