.bash_profile - start ssh-agent

.bash_profile

# adopted from https://confluence.atlassian.com/display/BITBUCKET/Set+up+SSH+for+Git#SetupSSHforGit-installpublickey, which was adopted from a GitHub script

if [ -r ~/.profile ]; then . ~/.profile; fi
case "$-" in *i*) if [ -r ~/.bashrc ]; then . ~/.bashrc; fi;; esac

echo
echo "Yo"
echo

SSH_ENV="$HOME/.ssh/environment"
  
# start the ssh-agent
function start_agent {
    echo "Initializing new SSH agent..."
    # spawn ssh-agent
    exec ssh-agent bash
    ssh-agent | sed 's/^echo/#echo/' > "$SSH_ENV"
    echo succeeded
    chmod 600 "$SSH_ENV"
    . "$SSH_ENV" > /dev/null
    ssh-add
}
  
# test for identities
function test_identities {
    # test whether standard identities have been added to the agent already
    ssh-add -l | grep "The agent has no identities" > /dev/null
    if [ $? -eq 0 ]; then
        ssh-add
        # $SSH_AUTH_SOCK broken so we start a new proper agent
        if [ $? -eq 2 ];then
            start_agent
        fi
    fi
}
  
# check for running ssh-agent with proper $SSH_AGENT_PID
if [ -n "$SSH_AGENT_PID" ]; then
    ps -ef | grep "$SSH_AGENT_PID" | grep ssh-agent > /dev/null
    if [ $? -eq 0 ]; then
    test_identities
    fi
# if $SSH_AGENT_PID is not properly set, we might be able to load one from
# $SSH_ENV
else
    if [ -f "$SSH_ENV" ]; then
    . "$SSH_ENV" > /dev/null
    fi
    ps -ef | grep "$SSH_AGENT_PID" | grep -v grep | grep ssh-agent > /dev/null
    if [ $? -eq 0 ]; then
        test_identities
    else
        start_agent
    fi
fi

For anyone stumbling upon this now, it's no longer necessary. See http://superuser.com/a/269570/393696

For anyone stumbling upon this now, it's no longer necessary. See http://superuser.com/a/269570/393696

No longer necessary for what? Mac users perhaps? What about everyone else? This works for Ubuntu WSL in Windows 10 and is very much necessary.