Mac:docker arman$ echo ${SSH_AUTH_SOCK}
/private/tmp/com.apple.launchd.MyXYPS94jn/Listeners
// без указания -v ${SSH_AUTH_SOCK}:${SSH_AUTH_SOCK} -e SSH_AUTH_SOCK="${SSH_AUTH_SOCK}"
Mac:docker arman$ docker-npm-container bash
root@acb1605bb805:/var/www/docker# echo ${SSH_AUTH_SOCK}
'' - пусто
// указал
root@2e10344f210d:/var/www/docker# echo ${SSH_AUTH_SOCK}
/private/tmp/com.apple.launchd.MyXYPS94jn/Listeners
root@2e10344f210d:/var/www/docker# ssh-add -l
Error connecting to agent: Connection refused
root@2e10344f210d:/var/www/docker# ${SSH_AUTH_SOCK}
bash: /private/tmp/com.apple.launchd.MyXYPS94jn/Listeners: Permission denied
docker run -it -v ${SSH_AUTH_SOCK}:${SSH_AUTH_SOCK} -e SSH_AUTH_SOCK="${SSH_AUTH_SOCK}"