How to create/write file under /usr in OS X 10.11 I was going to compile a php extension using phpize, but it reported some files not found. I googled and found some solutions, 


  In OS X 10.9, we can make a symbol link from /XCODE_PATH/OS_X_SDK/usr/include to /usr/include


But it seems that OS X 10.11 has some system policy which deny this operation. I even tried to boot in single user mode, but I just got 

$ sudo ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk/usr/include /usr/include
Sandbox: ln(14) System policy: deny(1) file-write-create /usr/include


Anyone knows how to fix this problem? Your answers or comments will be highly appreciated.
You can fight SIP, but probably not for long.

Why not just do it the recommended way and put in /usr/local/include