Ghostscript不可写

尝试在新Macbook上安装八度音,但使用Homebrew时遇到问题.我在这里遵循指示:http: //wiki.octave.org/Octave_for_MacOS_X

我遇到了错误:

Linking /usr/local/Cellar/ghostscript/9.14...
Error: Could not symlink share/ghostscript/Resource
/usr/local/share/ghostscript is not writable.

进入后:

sudo chown -R username:admin /usr/local/bin
brew link ghostscript

我仍然得到同样的错误.如何使ghostscript可写？