comm: fix comparison when reading from pipes#9545
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sylvestre merged 2 commits intouutils:mainfrom Jan 17, 2026
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could you please add a test to make sure we don't regress? thanks |
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Tried to add a test. On my machine (Linux, WSL2, devcontainer) the test fails if the fix is not applied: and passes with the applied fix in comm.rs. |
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@sylvestre : test added. please re-review. Failure in CI (windows-latest) is most likely independent of my changes. Could you please retrigger the job to be sure? |
Use case is that two files are piped into comm, i.e. in bash comm <(cat file1) <(cat file2) Before the fix, comm reads from the pipes twice. Once in "fn comm" and once in "fn are_files_identical". As such, part of the data is skipped in comparison which leads to wrong output. This is fixed by skipping the file comparison in case one of the files is not a regular file.
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@sylvestre : resolved merged conflicts, ready to be reviewed. |
mattsu2020
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Jan 23, 2026
* comm: fix comparison when reading from pipes Use case is that two files are piped into comm, i.e. in bash comm <(cat file1) <(cat file2) Before the fix, comm reads from the pipes twice. Once in "fn comm" and once in "fn are_files_identical". As such, part of the data is skipped in comparison which leads to wrong output. This is fixed by skipping the file comparison in case one of the files is not a regular file. * comm: add test for reading from pipes
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Use case is that two files are piped into comm, i.e. in bash
see also full example in #9537
Before the fix, comm reads from the pipes twice. Once in "fn comm" and
once in "fn are_files_identical". As such, part of the data is skipped
in comparison which leads to wrong output.
This is fixed by skipping the file comparison in case one of the files is not a regular file.
This fixes #9537