User's manual. Section 3.

PERMS(3): file permissions and permission checks


Files are described by directory entries as described in dir(3). Read that before reading the description of permission checks that follows.

Users and groups are defined by the authentication protocol spoken when dialing file systems. They are a local to each file tree.

In general, only bits 0777 are honored and their sematics are those used by UNIX for both files and directories, but for what follows.

When writing new file systems, the convention is to use zxc(1) as a the reference and [zx/perms(2)] to check for permissions.


User's manual. Section 3.