ssh-agent passphrase code example
Example 1: ssh agent remember passphrase
$ ssh-add .ssh/id_rsa
Enter passphrase for .ssh/id_rsa:
Identity added: .ssh/id_rsa (.ssh/id_rsa)
Example 2: ssh agent remember passphrase
$ ssh-add -l
$ ssh-add .ssh/id_rsa
Enter passphrase for .ssh/id_rsa:
Identity added: .ssh/id_rsa (.ssh/id_rsa)
$ ssh-add -l