# Unicorn 0.94.0 - small fixes and new features **URL:** \ **Category:** Ruby\ **Created:** [November 5, 2009, 11:07am UTC](https://www.ruby-forum.com/t/unicorn-0-94-0-small-fixes-and-new-features/178489 "2009-11-05T11:07:51Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![ericw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/e/97f17d/32.png) [@ericw](https://www.ruby-forum.com/u/ericw)\ **Post date:** [November 5, 2009, 11:07am UTC](https://www.ruby-forum.com/t/unicorn-0-94-0-small-fixes-and-new-features/178489/1 "2009-11-05T11:07:51Z")
Unicorn is a HTTP server for Rack applications designed to only serve fast clients on low-latency, high-bandwidth connections and take advantage of features in Unix/Unix-like kernels. Slow clients should only be served by placing a reverse proxy capable of fully buffering both the the request and response in between Unicorn and slow clients. - [http://unicorn.bogomips.org/](http://unicorn.bogomips.org/) - removed\_email\_address@domain.invalid - git://git.bogomips.org/unicorn.git Changes: The HTTP parser is fix for oddly-aligned reads of trailers (this technically affects headers, too, but is highly unlikely due to our non-support of slow clients). This allows our HTTP parser to better support very slow clients when used by other servers (like Rainbows!). Fortunately this bug does not appear to lead to any invalid memory accesses (and potential arbitrary code execution). FreeBSD (and possibly other \*BSDs) support is improved and and all the test cases pass under FreeBSD 7.2. Various flavors of GNU/Linux remains our primary platform for development and production. New features added include the “working\_directory” directive in the configurator . Even without specifying a “working\_directory”, symlink-aware detection of the current path no longer depends on /bin/sh so it should work out-of-the-box on FreeBSD and Solaris and not just systems where /bin/sh is dash, ksh93 or bash. User-switching support is finally supported but only intended for use in the after\_fork hook of worker processes. Putting it in the after\_fork hook allows allows users to set things like CPU affinity[1] on a per-worker basis before dropping privileges. The master process retains all privileges it started with. The ENV[“RACK\_ENV”] (process-wide) environment variable is now both read and set for `unicorn' in the same way RAILS_ENV is used by `unicorn\_rails’. This allows the Merb launcher to read ENV[“RACK\_ENV”] in [config.ru](http://config.ru). Other web servers already set this and there may be applications or libraries that already rely on this de facto standard. Eric W. (26): cleanup: avoid redundant error checks for fstat test\_helper: connect(2) may fail with EINVAL GNUmakefile: fix non-portable tar(1) usage tests: provide a pure Ruby setsid(8) equivalent more portable symlink awareness for START\_CTX[:cwd] test\_signals: avoid portability issues with fchmod(2) cleanup error handling and make it less noisy Do not override Dir.chdir in config files configurator: add “working\_directory” directive configurator: working\_directory is expanded configurator: set ENV[“PWD”] with working\_directory, too configurator: working\_directory affects pid, std{err,out}\_paths configurator: update documentation for working\_directory TODO: remove working\_directory bit, done Util.reopen\_logs: remove needless Range worker: user/group switching for after\_fork hooks Fix autoload of Etc in Worker for Ruby 1.9 bin/unicorn: allow RACK\_ENV to be passed from parent tests for RACK\_ENV preservation http: allow headers/trailers to be written byte-wise http: extra test for bytewise chunked bodies tee\_input: do not clobber trailer buffer on partial uploads test\_exec: ensure master is killed after test Util::tmpio returns a TmpIO that responds to #size TODO: remove user-switching bit, done unicorn 0.94.0 Wayne L. (1): bin/unicorn: set ENV[“RACK\_ENV”] on startup [1] - Unicorn does not support CPU affinity directly, but it is possible to load code that allows it inside after\_fork hooks, or even just call sched\_tool(8).