mkdir attempts to create a directory named pathname.
The parameter mode specifies the permissions to use. It is modified by
the process's umask in the usual way: the permissions of the created
directory are (mode & ~umask & 0777). Other mode bits of
the created directory depend on the operating system. For Linux, see below.
The newly created directory will be owned by the effective user ID of the
process. If the directory containing the file has the set group ID bit set, or
if the filesystem is mounted with BSD group semantics, the new directory will
inherit the group ownership from its parent; otherwise it will be owned by the
effective group ID of the process.
If the parent directory has the set group ID bit set then so will the newly
Under Linux apart from the permission bits, only the S_ISVTX mode bit is
honored. That is, under Linux the created directory actually gets mode
(mode & ~umask & 01777). See also stat(2).
There are many infelicities in the protocol underlying NFS. Some of these affect