Solutions of install RMagick on Mac OSX

Problem

• System: Mac OSX

Installing RMagick gems for ruby, get error:

yukis$ gem install rmagick
/Users/yukis/.rvm/rubies/ruby-1.9.3-p362/lib/ruby/1.9.1/yaml.rb:56:in `<top (required)>':
It seems your ruby installation is missing psych (for YAML output).
To eliminate this warning, please install libyaml and reinstall your ruby.
Building native extensions.  This could take a while...
ERROR:  Error installing rmagick:
    ERROR: Failed to build gem native extension.

        /Users/yukis/.rvm/rubies/ruby-1.9.3-p362/bin/ruby extconf.rb
checking for /usr/local/Cellar/apple-gcc42/4.2.1-5666.3/bin/gcc-4.2... yes
checking for Magick-config... no
checking for pkg-config... yes
Package MagickCore was not found in the pkg-config search path.
Perhaps you should add the directory containing `MagickCore.pc'
to the PKG_CONFIG_PATH environment variable
No package 'MagickCore' found
checking for outdated ImageMagick version (<= 6.4.9)... *** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
    --with-opt-dir
    --with-opt-include
    --without-opt-include=${opt-dir}/include
    --with-opt-lib
    --without-opt-lib=${opt-dir}/lib
    --with-make-prog
    --without-make-prog
    --srcdir=.
    --curdir
    --ruby=/Users/yukis/.rvm/rubies/ruby-1.9.3-p362/bin/ruby


Gem files will remain installed in /Users/yukis/.rvm/gems/ruby-1.9.3-p362/gems/rmagick-2.15.4 for inspection.
Results logged to /Users/yukis/.rvm/gems/ruby-1.9.3-p362/gems/rmagick-2.15.4/ext/RMagick/gem_make.out

Solution

1. check pkg-config (or reinstalling it)
2. run

C_INCLUDE_PATH=/usr/local/Cellar/imagemagick/6.9.2-6/include/ImageMagick-6 PKG_CONFIG_PATH=/usr/local/Cellar/imagemagick/6.9.2-6/lib/pkgconfig gem install rmagick

Reference