Brew Caveats的含義？

Question

這是什麼意思時，我沏安裝python

Caveats 
A CA file has been bootstrapped using certificates from the SystemRoots 
keychain. To add additional certificates (e.g. the certificates added in 
the System keychain), place .pem files in 
    /usr/local/etc/openssl/certs 

and run 
    /usr/local/opt/openssl/bin/c_rehash 

This formula is keg-only, which means it was not symlinked into /usr/local. 

Apple has deprecated use of OpenSSL in favor of its own TLS and crypto libraries 

Generally there are no consequences of this for you. If you build your 
own software and it requires this formula, you'll need to add to your 
build variables: 

    LDFLAGS: -L/usr/local/opt/openssl/lib 
    CPPFLAGS: -I/usr/local/opt/openssl/include 

1. 什麼.pem文件？
2. Keg-only，這是否意味着我需要在我的bash配置文件中鏈接brew python來引用brew安裝，而不是在mac python中構建？

Answer 1

1. pem文件證書文件（公鑰）;您通常需要他們在使用像TLS/SSL這樣的加密技術時驗證遠程端的真實性（例如https://）。您可能試過Google搜尋"PEM file"，這可能會引導您到What is a Pem file and how does it differ from other OpenSSL Generated Key File Formats?

2. keg-only意味着這樣安裝的軟件包不會污染全局命名空間（所以你不能偶然使用它，並打破事情）。 可能使用brew安裝的python的最簡單方法是在您的.bashrc中將/usr/local/opt/python/bin/（或類似的，我沒有brew現在可用）添加到您的PATH變量中。 （需要在bash的個人資料的情況下鏈接沖泡蟒蛇並沒有太大的意義;同時，你應該使用術語符號鏈接而不是鏈接以避免歧義）