rust-lang / rust-lang/libc

Wrong size types for `struct flock` constants

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#1,619 5 comments 1 reaction 1 assignee View on GitHub

@LusterSourav is already working on this.

Since Aug 11, 2026.

C-bug S-waiting-on-decision
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Rust
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Description

On x86_64 Linux (at least; I haven't looked at all at other platforms), F_(RD|WR|UN)LCK and SEEK_(SET|CUR|END) are all defined as c_int. However, the flock struct uses c_short for the fields that they go in. man 2 fcntl, section 'Advisory record locking', and POSIX confirm that they should be short, not int.

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