rustix/fs/seek_from.rs
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//! The following is derived from Rust's
//! library/std/src/io/mod.rs at revision
//! dca3f1b786efd27be3b325ed1e01e247aa589c3b.
/// Enumeration of possible methods to seek within an I/O object.
///
/// It is used by the [`seek`] function.
///
/// This is similar to [`std::io::SeekFrom`], however it adds platform-specific
/// seek options.
///
/// [`seek`]: crate::fs::seek
#[derive(Copy, PartialEq, Eq, Clone, Debug)]
#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
pub enum SeekFrom {
/// Sets the offset to the provided number of bytes.
#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
Start(#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))] u64),
/// Sets the offset to the size of this object plus the specified number of
/// bytes.
///
/// It is possible to seek beyond the end of an object, but it's an error
/// to seek before byte 0.
#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
End(#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))] i64),
/// Sets the offset to the current position plus the specified number of
/// bytes.
///
/// It is possible to seek beyond the end of an object, but it's an error
/// to seek before byte 0.
#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
Current(#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))] i64),
/// Sets the offset to the current position plus the specified number of
/// bytes, plus the distance to the next byte which is not in a hole.
///
/// If the offset is in a hole at the end of the file, the seek will fail
/// with [`Errno::NXIO`].
///
/// [`Errno::NXIO`]: crate::io::Errno::NXIO
#[cfg(any(apple, freebsdlike, linux_kernel, solarish))]
Data(i64),
/// Sets the offset to the current position plus the specified number of
/// bytes, plus the distance to the next byte which is in a hole.
///
/// If there is no hole past the offset, it will be set to the end of the
/// file i.e. there is an implicit hole at the end of any file.
#[cfg(any(apple, freebsdlike, linux_kernel, solarish))]
Hole(i64),
}