How to fix an error “RPC failed; curl 56 LibreSSL SSL_read: SSL_ERROR_SYSCALL, errno 54” due to Git remote end hung up unexpectedly

I was getting a following undesired error message when I was trying to install HomeBrew on my new MacBook Pro:

RPC failed; curl 56 LibreSSL SSL_read: SSL_ERROR_SYSCALL, errno 54

Well, this was unexpected. This error occurs most likely due to your git buffer connection dropped most likely due to your internet connection, meaning that the buffer carrying a data gets lost due to a slow internet connection or a proxy.

Although the simplest possible solution is to retry your command again, but, if that does not work, one solution you can try is to increase your git buffer with the following command:

git config http.postBuffer 531288000

where the number 531288000 is the number representing maximum size in bytes of the buffer used by smart HTTP transports when POSTing data to the remote system. You can read more about it in:

Git - git-config Documentation