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grep: -F -f rejects a pattern file that contains invalid UTF-8

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
62/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
rust
Domain
cli

Research direction

Start by locating the code that loads patterns for fixed-string mode (-F -f), then compare its byte handling with the behavior discussed in #64 and #75. Run the issue’s commands and check the exit status and output bytes; done means uutils exits 0 and writes ff 0a for the invalid-UTF-8 pattern and input.

Written by the indexing model from the issue text.

Description

bug

uutils decodes a pattern file as UTF-8 even when the patterns are fixed strings. GNU matches the bytes.

$ printf '\377\n' > patterns; printf '\377\n' > input
$ LC_ALL=C grep -aF -f patterns input > out.bin; status=$?
$ echo "status=$status"; od -An -tx1 out.bin

GNU grep 3.12 exits 0 and writes ff 0a. uutils reports grep: patterns: stream did not contain valid UTF-8, exits 2, and writes nothing. The result is the same with LC_ALL=C.UTF-8.

#64 and the closed #75 discuss byte and locale handling more generally.

Dominant language
Rust
Stars
133
Forks
25
Avg merge
19h 49m
Merged PRs (30d)
11

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  4. Open a pull request that references the issue number.

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