A Ruby interface for the Apple system logger.

gem install apple-system-logger

gem cert --add <(curl -Ls https://raw.githubusercontent.com/djberg96/apple-system-logger/main/certs/djberg96_pub.pem)

require 'apple-system-logger'

# With defaults
log = Apple::System::Logger.new
log.warn("This is a warning")

# With all possible options, including multicast to $stderr
log = Apple::System::Logger.new(
  facility: 'com.apple.console',
  level: Apple::System::Logger::ASL_LEVEL_WARNING,
  progname: 'myprog',
  logdev: $stderr
)

log.warn("This is also a warning")

# Search for logs
log = Apple::System::Logger.new
results = log.search(:sender => 'bootlog', :level => 5)

# Always do this when finished, or use the block version of the constructor
log.close

Apache-2.0

It does not seem that you can multicast to any fileno except stdout and stderr. I am not sure if this is by design, or if I am missing something, because the API does not explicitly forbid other file descriptors, nor does it raise an error.

(C) 2020-2026 Daniel J. Berger, All Rights Reserved

This package is provided "as is" and without any express or implied warranties, including, without limitation, the implied warranties of merchantability and fitness for a particular purpose.

Daniel J. Berger