背景：因为某些原因需要从本地mac连接远程linxu桌面查看一些内容，必须使用桌面查看，所以ssh无法满足，所以决定安装vnc客户端。
问题：
在mac上通过 brew install tiger-vnc命令安装, 但是报错如下：
bash
==> Downloading https://raw.githubusercontent.com/Homebrew/homebrew-core/555c288aed70eaa4fa9dcf3bd37a1fbca3f69a00/Formula/lib/libpng.rb
Already downloaded: /Users/xxxx/Library/Caches/Homebrew/downloads/e334b6d4753af38f07dcbd30e22cd79df1d2b2c61cd4ac212c64559271884d04--libpng.rb
==> Downloading https://downloads.sourceforge.net/project/libpng/libpng16/1.6.44/libpng-1.6.44.tar.xz
################################################################################################################################################################################ 100.0%curl: (35) error:06FFF089:digital envelope routines:CRYPTO_internal:bad key length
Trying a mirror...
==> Downloading https://sourceforge.mirrorservice.org/l/li/libpng/libpng16/1.6.44/libpng-1.6.44.tar.xz
curl: (6) Could not resolve host: sourceforge.mirrorservice.org
Warning: Problem : timeout. Will retry in 1 seconds. 3 retries left.
curl: (6) Could not resolve host: sourceforge.mirrorservice.org
Warning: Problem : timeout. Will retry in 2 seconds. 2 retries left.
curl: (6) Could not resolve host: sourceforge.mirrorservice.org
Warning: Problem : timeout. Will retry in 4 seconds. 1 retries left.
curl: (6) Could not resolve host: sourceforge.mirrorservice.org
Error: tiger-vnc: Failed to download resource "libpng"
尝试的解决办法：
在stackoverflow有类似的curl: (35) error:06FFF089:digital envelope routines:CRYPTO_internal:bad key length， 但是根据该方法无法解决我的问题。
link：https://stackoverflow.com/questions/69734654/fixing-git-https-error-bad-key-length-on-macos-12
该link给的方法是export CURL_SSL_BACKEND="secure-transport"
再次尝试修改brew缓存目录内容，将下载的libpng-1.6.44.tar.xz直接放入到cache目录（通过brew --cache 获取cache目录信息），依然报相同的错误。
最终解决办法：
升级mac os版本， 我的版本是12.1， 直接升级到了12.7.6， 问题解决，
为什么选择升级os，因为stackoverflow的帖子写的该问题时，有一段描述：macOS 12.3 was officially released on march 13th, 2022 and the issue reported on this question has been fixed. Personally I have removed the workaround I had deployed and I suggest others do the same to keep up with the new versions.
而我的mac版本是12.1，所以最后决定升级，当时12.x系列中可用的版本是12.7.6， 就升级到12.7.6