File permissions

The following are common file and directory permission commands and codes in Linux.

1 File Permission commands

Command	Function
chmod -c -R	Assign a file read, write, and execute permissions
chmod -R 777 [dir]	Assign full permission recursively to the directory and all sub-directories
chmod -x file	Remove the execution permission of any file
chmod [±]t dir	Add or remove stticky bit, whereby files in a directory can only be renamed or removed by owner or root
g\|a] +/- [r\|w\|x]	Change privileges for user, group, or all to read, write, or execute
chmod 755 file	Grant the file owner read, write, and execute permissions; othres have only read and execute permissions
chmod 766 file	Grant the file owner full read, write and execute permissions, while group and other users can only read and execute.
chmod 777 file	Grant full (read, write, and execute) permission to everyone
chmod u-x	Remove executable privileges from user
chmod u+x	Assign executable privileges to user
chown -c -R	Change ownership of a file; changes apply recursively to directory contents
chown -R user:group dir	Change owner and group ownership of the directory and all sub-directories
chown user file	Change ownership of a file
chown user file	Change the ownership of a file
chown user:group file	Change user and group privileges of a file
chown root /u	Transfer ownership of a file to the root user
touch -a -t	Create or modify a file timestamp
umask xxxx	Set default permissions to a directory