Crate getattrlistbulk 

getattrlistbulk

Safe Rust bindings for the macOS getattrlistbulk() system call.

This crate provides high-performance directory enumeration by retrieving file metadata in bulk, reducing the number of syscalls from O(n) to O(n/batch_size).

Performance

Approach	Complexity	10K Files
Traditional (readdir + stat)	O(n)	~20,000 syscalls
getattrlistbulk	O(n/batch)	~12 syscalls

~1,600x fewer syscalls → ~4x faster on NVMe SSDs (up to 50x on network storage).

Traditional:  opendir() → [readdir() + stat()] × N → closedir()
This crate:   open() → getattrlistbulk() × ceil(N/800) → close()

Run cargo bench --bench compare for reproducible benchmarks on your hardware.

Example

use getattrlistbulk::{read_dir, RequestedAttributes};

let attrs = RequestedAttributes {
    name: true,
    size: true,
    ..Default::default()
};

for entry in read_dir("/Users", attrs).unwrap() {
    let entry = entry.unwrap();
    println!("{}: {} bytes", entry.name, entry.size.unwrap_or(0));
}

Platform Support

This crate only compiles on macOS. Attempting to compile on other platforms will result in a compile-time error.

Structs

DirEntries

Iterator over directory entries.

DirEntry

Metadata for a single directory entry.

DirReader

Builder for configuring directory reads.

RequestedAttributes

Attributes to request for each directory entry.

Enums

Error

Error type for directory operations.

ObjectType

Type of filesystem object.

Functions

read_dir

Read directory entries with specified attributes.

read_dir_with_buffer

Read directory entries with custom buffer size.