Enable ssh-agent automatic launch and sharing between multiple git-bash instances (windows, git-bash)

.bashrc

# Enable ssh-agent automatic launch and sharing between multiple git-bash instances
#
# Env vars used
# SSH_AUTH_SOCK - ssh-agent socket, should be set for ssh-add or git to be able to connect
# SSH_AGENT_PID - ssh-agent process id, should be set in order to check that it is running
# SSH_AGENT_ENV - env file path to share variable between instances of git-bash
SSH_AGENT_ENV=~/ssh-agent.env
# import env file and supress error message if it does not exist
. $SSH_AGENT_ENV 2> /dev/null

# if we know that ssh-agent was launched before ($SSH_AGENT_PID is set) and process with that pid is running 
if [ -n "$SSH_AGENT_PID" ] && ps -p $SSH_AGENT_PID > /dev/null 
then
  # we don't need to do anything, ssh-add and git will properly connect since we've imported env variables required
  echo "Connected to ssh-agent"
else   
  # start ssh-agent and save required vars for sharing in $SSH_AGENT_ENV file
  eval $(ssh-agent) > /dev/null
  echo export SSH_AUTH_SOCK=\"$SSH_AUTH_SOCK\" > $SSH_AGENT_ENV
  echo export SSH_AGENT_PID=$SSH_AGENT_PID >> $SSH_AGENT_ENV
  echo "Started ssh-agent"
fi