mysql2 和 ruby 1.9.2 的错误处理

[quote]
OS Version: Mac OS X 10.7.1 Lion
Ruby Version: ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-darwin11.1.0]
Ruby Location: /usr/local/rvm/bin/ruby
Rails Version: Rails 3.1.0
Rails Location: /usr/local/rvm/gems/ruby-1.9.2-p290/bin/rails
[/quote]

错误提示
[quote]
/usr/local/rvm/gems/ruby-1.9.2-p290/gems/mysql2-0.3.7/lib/mysql2.rb:9:in `require': dlopen(/usr/local/rvm/gems/ruby-1.9.2-p290/gems/mysql2-0.3.7/lib/mysql2/mysql2.bundle, 9): Library not loaded: libmysqlclient.18.dylib (LoadError)
Referenced from: /usr/local/rvm/gems/ruby-1.9.2-p290/gems/mysql2-0.3.7/lib/mysql2/mysql2.bundle
Reason: image not found - /usr/local/rvm/gems/ruby-1.9.2-p290/gems/mysql2-0.3.7/lib/mysql2/mysql2.bundle
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/mysql2-0.3.7/lib/mysql2.rb:9:in `'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.18/lib/bundler/runtime.rb:68:in `require'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.18/lib/bundler/runtime.rb:68:in `block (2 levels) in require'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.18/lib/bundler/runtime.rb:66:in `each'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.18/lib/bundler/runtime.rb:66:in `block in require'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.18/lib/bundler/runtime.rb:55:in `each'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.18/lib/bundler/runtime.rb:55:in `require'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.18/lib/bundler.rb:120:in `require'
from /Users/doug/Sites/simple_cms/config/application.rb:7:in `'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.0/lib/rails/commands.rb:52:in `require'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.0/lib/rails/commands.rb:52:in `block in '
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.0/lib/rails/commands.rb:49:in `tap'
from /usr/local/rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.0/lib/rails/commands.rb:49:in `'
from script/rails:6:in `require'
from script/rails:6:in `

'
[/quote]
解决办法

sudo install_name_tool -change libmysqlclient.18.dylib /usr/local/mysql/lib/libmysqlclient.18.dylib /Users/keo/.rvm/gems/ruby-1.9.2-p290/gems/mysql2-0.3.7/lib/mysql2/mysql2.bundle

还有一个装mongrel的出错

出错提示如下：
[quote]
ding native extensions. This could take a while...
ERROR: Error installing mongrel:
ERROR: Failed to build gem native extension.

/usr/local/bin/ruby extconf.rb install mongrel
checking for main() in -lc... yes
creating Makefile

make
gcc -I. -I/usr/local/include/ruby-1.9.1/i386-darwin9.7.0 -I/usr/local/include/ruby-1.9.1/ruby/backward -I/usr/local/include/ruby-1.9.1 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -D_XOPEN_SOURCE=1 -O2 -g -Wall -Wno-parentheses -fno-common -pipe -fno-common -o http11.o -c http11.c
http11.c: In function 'http_field':
http11.c:77: error: 'struct RString' has no member named 'ptr'
http11.c:77: error: 'struct RString' has no member named 'len'
http11.c:77: warning: left-hand operand of comma expression has no effect
http11.c:77: warning: statement with no effect
http11.c: In function 'header_done':
http11.c:172: error: 'struct RString' has no member named 'ptr'
http11.c:174: error: 'struct RString' has no member named 'ptr'
http11.c:176: error: 'struct RString' has no member named 'ptr'
http11.c:177: error: 'struct RString' has no member named 'len'
http11.c: In function 'HttpParser_execute':
http11.c:298: error: 'struct RString' has no member named 'ptr'
http11.c:299: error: 'struct RString' has no member named 'len'
make: *** [http11.o] Error 1
[/quote]
问题是要装pre的mongrel才能1.9.2 rails 3.1

$ sudo gem1.9 install mongrel --pre
> Building native extensions.  This could take a while...
> Successfully installed mongrel-1.2.0.pre2
> 1 gem installed

最好是改gemfile如下：

gem 'mongrel','~> 1.2.0.pre2'