23 lines
803 B
Rust
23 lines
803 B
Rust
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//! I/O utilities.
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use anyhow::Error;
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use proxmox::tools::fd::Fd;
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/// The `BufferedRead` trait provides a single function
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/// `buffered_read`. It returns a reference to an internal buffer. The
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/// purpose of this traid is to avoid unnecessary data copies.
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pub trait BufferedRead {
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/// This functions tries to fill the internal buffers, then
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/// returns a reference to the available data. It returns an empty
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/// buffer if `offset` points to the end of the file.
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fn buffered_read(&mut self, offset: u64) -> Result<&[u8], Error>;
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}
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/// safe wrapper for `nix::unistd::pipe2` defaulting to `O_CLOEXEC` and guarding the file
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/// descriptors.
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pub fn pipe() -> Result<(Fd, Fd), Error> {
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let (pin, pout) = nix::unistd::pipe2(nix::fcntl::OFlag::O_CLOEXEC)?;
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Ok((Fd(pin), Fd(pout)))
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}
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