我正在尝试在mac上安装gdb，似乎是一个又一个问题。对于初学者来说，我在系统上安装了X-Code命令行工具。当我最初运行gdb时，我会得到
gdb: command not found
k所以我继续安装它
brew install gdb
进行安装并提出以下问题
Error: The `brew link` step did not complete successfully
The formula built, but is not symlinked into /usr/local
Could not symlink share/info/annotate.info
/usr/local/share/info is not writable.
You can try again using:
brew link gdb
所以我再试一次，
brew link gdb
Linking /usr/local/Cellar/gdb/7.8...
Error: Could not symlink share/info/annotate.info
/usr/local/share/info is not writable.
I try giving write permission to the folder
cd /usr/local/share/info
因此，我做了它想要我做的事，
| => chmod +r annotate.info
chmod: annotate.info: No such file or directory
传奇继续，现在我站在哪里
| => brew install gdb
Warning: gdb-7.8 already installed, it's just not linked
如何链接gdb并使其正常工作。任何帮助表示赞赏。