# buffered\_offset\_reader

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Rust crate for buffered reading of a file at arbitrary offsets.

Uses `std::os::unix::fs::FileExt::read_at()` on unix (aka `pread()`)
or `std::os::windows::fs::FileExt::seek_read()` on windows to do thread-safe
reads of the underlying file.

## Examples

```rust
use buffered_offset_reader::{BufOffsetReader, OffsetReadMut};
use std::fs::File;

fn main() -> std::io::Result<()> {
    let f = File::open("log.txt")?;
    let mut reader = BufOffsetReader::new(f);
    let mut tmp = vec![0; 8];

    reader.read_at(&mut tmp, 0)?;  // read 8 bytes at offset 0

	// This read will be fulfilled by the reader's internal buffer,
	// so it won't require a system call.
    reader.read_at(&mut tmp, 32)?; // read 8 bytes at offset 32

    Ok(())
}
```