# Based on ssh-agent code
 
 local GPG_ENV=$HOME/.gnupg/gpg-agent.env
 
 function start_agent {
   /usr/bin/env gpg-agent --daemon --enable-ssh-support --write-env-file ${GPG_ENV} > /dev/null
   chmod 600 ${GPG_ENV}
   . ${GPG_ENV} > /dev/null
 }
 
 # Source GPG agent settings, if applicable
 if [ -f "${GPG_ENV}" ]; then
   . ${GPG_ENV} > /dev/null
   ps -ef | grep ${SSH_AGENT_PID} | grep gpg-agent > /dev/null || {
     start_agent;
   }
 else
   start_agent;
 fi
 
 export GPG_AGENT_INFO
 export SSH_AUTH_SOCK
 export SSH_AGENT_PID
 
 GPG_TTY=$(tty)
 export GPG_TTY