折腾：
【未解决】Mac中通过brew升级rsync
期间：
➜ output brew tap homebrew/dupes Error: homebrew/dupes was deprecated. This tap is now empty as all its formulae were migrated.
Error: homebrew/dupes was deprecated. This tap is now empty as all its formulae were migrated.
暂时不太懂，不知道如何解决。
不过，后来无意间想到，能否通过upgrade升级rsync？
所以去搜：
mac upgrade rsync
直接去安装试试：
➜ output brew install rsync ==> Downloading https://homebrew.bintray.com/bottles/rsync-3.1.3_1.high_sierra.bottle.tar.gz ######################################################################## 100.0% ==> Pouring rsync-3.1.3_1.high_sierra.bottle.tar.gz 🍺 /usr/local/Cellar/rsync/3.1.3_1: 9 files, 756.1KB ➜ output which rsync /usr/local/bin/rsync ➜ output rsync --version rsync version 2.6.9 protocol version 29 Copyright (C) 1996-2006 by Andrew Tridgell, Wayne Davison, and others. < http://rsync.samba.org/ > Capabilities: 64-bit files, socketpairs, hard links, symlinks, batchfiles, inplace, IPv6, 64-bit system inums, 64-bit internal inums rsync comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions. See the GNU General Public Licence for details.
发现虽然安装成功，但是rsync还是旧的
参考上贴提到的：
感觉需要重启终端
去：
source ~/.bashrc
果然就可以了：
➜ output source ~/.bashrc ➜ output which rsync /usr/local/bin/rsync ➜ output rsync --version rsync version 3.1.3 protocol version 31 Copyright (C) 1996-2018 by Andrew Tridgell, Wayne Davison, and others. Web site: http://rsync.samba.org/ Capabilities: 64-bit files, 64-bit inums, 64-bit timestamps, 64-bit long ints, socketpairs, hardlinks, symlinks, IPv6, batchfiles, inplace, append, ACLs, xattrs, iconv, symtimes, no prealloc, file-flags rsync comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions. See the GNU General Public Licence for details.
至此，基本上明白了：
【总结】
Mac自带的rsync的旧版本的。
想要通过brew安装新版本。
直接通过brew去upgrade会失败：
Error: rsync not installed
而参考别人（之前稍早）的做法，去：
brew tap homebrew/dupes
希望可以增加额外的homebrew的dupes仓库，结果又出错：
Error: homebrew/dupes was deprecated. This tap is now empty as all its formulae were migrated
实际上是因为：
homebrew的dupes仓库，已经取消掉了，其中的内容已合并到homebrew的core中了。
而当前此处mac中brew的仓库有哪些，可以通过：
brew tap
看到是：
homebrew/core
-》说明之前位于homebrew/dupes的rsync，已经被合并到了，此处已经rsync中自带的仓库homebrew/core中了。
-》所以，就没必要再去：
brew tap homebrew/dupes
了。
转载请注明：在路上 » 【已解决】brew tap homebrew/dupes出错：Error: homebrew/dupes was deprecated. This tap is now empty as all its formulae were migrated