Groups in macos

sudo dscl . -create /groups/newgroupname
sudo dscl . -append /groups/newgroupname gid 4200

Creates a new group. Alternatively use System Preferences -> Users and Groups

id -Gn emiliko

List all the groups emiliko belongs to

sudo chmod -R g=u .

Set the group privileges of the file hierarchy rooted at . to be the same as the user. Very nice to convert a directory to be editable by ssh users