NAME
mkdir - make a directory file

SYNOPSIS
mkdir(path, mode)
const char *path;
int mode;

DESCRIPTION
Mkdir creates a new directory file with name path. The mode of the
new file is initialized from mode. (The protection part of the
mode is modified by the process’s mode mask; see umask(2)).

The directory’s owner ID is set to the process’s effective user ID.
The directory’s group ID is set to that of the parent directory in
which it is created.

The low-order 9 bits of mode are modified by the process’s file
mode creation mask: all bits set in the process’s file mode
creation mask are cleared. See umask(2).

RETURN VALUE
A 0 return value indicates success. A -1 return value indicates an
error, and an error code is stored in errno.

ERRORS
Mkdir will fail and no directory will be created if:

[ENOTDIR] A component of the path prefix is not a directory.

[EINVAL] The pathname contains a character with the high-
order bit set.

[ENAMETOOLONG] A component of a pathname exceeded 255 characters,
or an entire path name exceeded 1023 characters.

[ENOENT] A component of the path prefix does not exist.

[EACCES] Search permission is denied for a component of the
path prefix.

[ELOOP] Too many symbolic links were encountered in
translating the pathname.

[EPERM] The path argument contains a byte with the high-
order bit set.

[EROFS] The named file resides on a read-only file system.

[EEXIST] The named file exists.

[ENOSPC] The directory in which the entry for the new
directory is being placed cannot be extended because
there is no space left on the file system containing
the directory.

[ENOSPC] The new directory cannot be created because there
there is no space left on the file system that will
contain the directory.

[ENOSPC] There are no free inodes on the file system on which
the directory is being created.

[EDQUOT] The directory in which the entry for the new
directory is being placed cannot be extended because
the user’s quota of disk blocks on the file system
containing the directory has been exhausted.

[EDQUOT] The new directory cannot be created because the
user’s quota of disk blocks on the file system that
will contain the directory has been exhausted.

[EDQUOT] The user’s quota of inodes on the file system on
which the directory is being created has been
exhausted.

[EIO] An I/O error occurred while making the directory
entry or allocating the inode.

[EIO] An I/O error occurred while reading from or writing
to the file system.

[EFAULT] Path points outside the process’s allocated address
space.