$ curl cheat.sh/
# setfacl
# Set file access control lists (ACL).
# More information: <https://manned.org/setfacl>.

# Modify ACL of a file for user with read and write access:
setfacl -m u:username:rw file

# Modify default ACL of a file for all users:
setfacl -d -m u::rw file

# Remove ACL of a file for a user:
setfacl -x u:username file

# Remove all ACL entries of a file:
setfacl -b file

$
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