apparently github has deprecated older TLS protocols,
when attempting to use git geting error
fatal: unable to access 'https://github.com/git/git/': error:1407742E:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version
seemingly the answer is to upgrade curl (which also updates openssl), and git
$ curl --version curl 7.24.0 (x86_64-apple-darwin12.0) libcurl/7.24.0 OpenSSL/0.9.8y zlib/1.2.5 Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtsp smtp smtps telnet tftp Features: AsynchDNS GSS-Negotiate IPv6 Largefile NTLM NTLM_WB SSL libz $ sudo port install curl
...now is downloading and installing etc etc etc ...
open new window $ curl --version curl 7.59.0 (x86_64-apple-darwin12.6.0) libcurl/7.59.0 OpenSSL/1.0.2o zlib/1.2.11 libidn2/2.0.4 libpsl/0.20.1 (+libidn2/2.0.4) Release-Date: 2018-03-14 Protocols: dict file ftp ftps gopher http https imap imaps pop3 pop3s rtsp smb smbs smtp smtps telnet tftp Features: AsynchDNS IDN IPv6 Largefile NTLM NTLM_WB SSL libz TLS-SRP UnixSockets HTTPS-proxy PSL
also necessary seems to be updating git, the latest available for Mountain Lion is too old
$ git --version
git version 2.3.5
so it becomes necessary for downloading https://github.com/git/git, going into such directory and making
$ /Volumes/whereever/new/version/is/git --version
git version 2.17.GIT
using this newly made version is now succesful for such as cloning
$ /Volumes/whereever/new/version/is/git clone https://github.com/git/git
installing via command line is not effective ($ make install), the version of git is not updated in this case.
so i will have to sort that out later ..