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mkdir() - Unix, Linux System Call
mkdir - create a directory
int mkdir(const char *pathname, mode_t mode);
mkdir() attempts to create a directory named
mode specifies the permissions to use. It is modified by the processs
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 created directory.
mkdir() returns zero on success, or -1 if an error occurred (in which case,
errno is set appropriately).
The parent directory does not allow write permission to the process,
or one of the directories in
pathname did not allow search permission.
pathname already exists (not necessarily as a directory).
This includes the case where
pathname is a symbolic link, dangling or not.
pathname points outside your accessible address space. |
Too many symbolic links were encountered in resolving
pathname was too long. |
A directory component in
pathname does not exist or is a dangling symbolic link.
Insufficient kernel memory was available.
The device containing
pathname has no room for the new directory.
The new directory cannot be created because the users disk quota is
A component used as a directory in
pathname is not, in fact, a directory.
The filesystem containing
pathname does not support the creation of directories.
pathname refers to a file on a read-only filesystem.
SVr4, BSD, POSIX.1-2001.
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
There are many infelicities in the protocol underlying NFS. Some
of these affect