1.问题
换了个wifi，git clone拉取代码就会报错，切回原来的wifi，又是可以的，反复尝试，最终确认，这个特定的wifi下，网页和命令行都不能访问github，甚是神奇。
G:\mylearn\source-code>git pull
ssh: connect to host github.com port 22: Connection timed out
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
G:\mylearn\source-code>ssh -T [email protected]
ssh: connect to host github.com port 22: Connection timed out
2.解决方案：
在C:\Users\wangzx\.ssh目录下，也就是放这个的目录下：
创建一个文件，config，不需要后缀名，内容为：
Host github.com
User [email protected]
Hostname ssh.github.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa
Port 443
添加完后如下：
G:\mylearn\source-code>ssh -T [email protected]
The authenticity of host '[ssh.github.com]:443 ([192.30.253.122]:443)' can't be established.
RSA key fingerprint is SHA256:nThbg6kXUpJWGl7E1IGOCspRomTxdCARLviKw6E5SY8.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '[ssh.github.com]:443,[192.30.253.122]:443' (RSA) to the list of known hosts.
Hi lightClouds917! You've successfully authenticated, but GitHub does not provide shell access.
G:\mylearn\source-code>ssh -T [email protected]
Hi lightClouds917! You've successfully authenticated, but GitHub does not provide shell access.
G:\mylearn\source-code>git pull
Warning: Permanently added the RSA host key for IP address '[192.30.253.123]:443' to the list of known hosts.
Already up-to-date.
G:\mylearn\source-code>git pull
Already up-to-date.
搞定！