以太坊开发教程- truffle安装

waterwdeMacBook-Pro:mytoken waterw$ npm install -g truffle
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/truffle
npm ERR! path /usr/local/lib/node_modules/truffle
npm ERR! code EACCES
npm ERR! errno -13
npm ERR! syscall access
npm ERR! Error: EACCES: permission denied, access '/usr/local/lib/node_modules/truffle'
npm ERR!  { [Error: EACCES: permission denied, access '/usr/local/lib/node_modules/truffle']
npm ERR!   stack:
npm ERR!    "Error: EACCES: permission denied, access '/usr/local/lib/node_modules/truffle'",
npm ERR!   errno: -13,
npm ERR!   code: 'EACCES',
npm ERR!   syscall: 'access',
npm ERR!   path: '/usr/local/lib/node_modules/truffle' }
npm ERR!
npm ERR! The operation was rejected by your operating system.
npm ERR! It is likely you do not have the permissions to access this file as the current user
npm ERR!
npm ERR! If you believe this might be a permissions issue, please double-check the
npm ERR! permissions of the fi