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DEPRECATION NOTICE

Please note that this repository has been deprecated and is no longer actively maintained by Polyverse Corporation. It may be removed in the future, but for now remains public for the benefit of any users.

Importantly, as the repository has not been maintained, it may contain unpatched security issues and other critical issues. Use at your own risk.

While it is not maintained, we would graciously consider any pull requests in accordance with our Individual Contributor License Agreement. https://github.com/polyverse/contributor-license-agreement

For any other issues, please feel free to contact info@polyverse.com


Build Status

rmesg

A 'dmesg' implementation in Rust

As a command-line utility

Obtain the latest release binary

wget https://github.com/polyverse/rmesg/releases/latest/download/rmesg
chmod a+x ./rmesg
# Optionally move to a stable location
mv ./rmesg /usr/local/bin

Cargo Install

cargo install rmesg

Usage

rmesg: A 'dmesg' port onto Rust 1.0.0
Archis Gore <archis@polyverse.com>
Reads (and prints) the kernel log buffer. Does not support all dmesg options (yet).

USAGE:
    rmesg [FLAGS] [OPTIONS]

FLAGS:
    -c               Clear ring buffer after printing (only when using klogctl)
    -f               When specified, follows logs (like tail -f)
    -h, --help       Prints help information
    -r               Print raw data as it came from the source backend.
    -V, --version    Prints version information

OPTIONS:
    -b <backend>        Select backend from where to read the logs. klog is the syslog/klogctl system call through libc.
                        kmsg is the /dev/kmsg file. [possible values: klogctl, devkmsg]

As a Crate

The real value of this crate is programmatic access to kernel buffer from Rust programs, allowing a dmesg that can be consumed programmatically.

The complete API can be found in the main.rs file which uses the sync/async versions of the APIs, both single-shot and iterative.

Depend on the rmesg crate

Include it in Cargo.toml:

[dependencies]
rmesg = "1.0.0"

Suppots two features:

  • async - Exposes asynchronous Stream API
  • sync - Exposes synchronous Iterator API

Reading the buffer single-shot (non-blocking)

NOTE: Reading single-shot is the same interface for sync or async

    use rmesg;

    // Read all logs as one big string with line-breaks
    let raw = rmesg::logs_raw(opts.backend, opts.clear).unwrap();
    print!("{}", raw)

    // Read logs as a Vec of Entry'ies (`Vec<Entry>`)
    // and can be processed entry-by-entry
    let entries = rmesg::log_entries(opts.backend, opts.clear).unwrap();
    for entry in entries {
        println!("{}", entry)
    }

Indefinitely iterating

With feature sync (i.e. synchronous), provides an Iterator over Result<Entry, RMesgError>.

    use rmesg;

    let entries = rmesg::logs_iter(opts.backend, opts.clear, opts.raw)?;
    for maybe_entry in entries {
        let entry = maybe_entry?;
        println!("{}", entry);
    }

With feature async (i.e. asynchronous), provides a Stream over Result<Entry, RMesgError>.

    use rmesg;

    // given that it's a stream over Result's, use the conveniences provided to us
    use futures_util::stream::TryStreamExt;

    let mut entries = rmesg::logs_stream(opts.backend, opts.clear, opts.raw).await?;

    while let Some(entry) = entries.try_next().await? {
        println!("{}", entry);
    }