Crate fileslice

source · [−]
Expand description

Slices of files

FileSlice is to File what Bytes is to Vec<u8>. Advantages over File:

  • You can slice it, reducing the scope to a range within the original file
  • Cloning is cheap (atomic addition; no syscall)
  • Seeking is very cheap (normal addition; no syscall)
  • Clones can’t affect each other at all (the fd’s real cursor is never used).

Optional features

Optional integrations for crates which naturally benefit from file slicing:

  • tar: Adds a slice_tarball helper method for splitting up a tar::Archive into a bunch of FileSlices.
  • parquet: Adds a ChunkReader impl for FileSlice. A parquet file contains many pages, and the decoder needs to interleave reads from these pages. The ChunkReader impl for File accomplishes this by making many clones of the fd. Using FileSlice instead lets you open ~7 as many parquet files before you hit your fd limit.

Structs

FileSlice

A slice of a file

Functions

slice_tarball