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MKNOD(2)		  FreeBSD System Calls Manual		      MKNOD(2)

     mknod, mknodat -- make a special file node

     Standard C	Library	(libc, -lc)

     #include <sys/stat.h>

     mknod(const char *path, mode_t mode, dev_t	dev);

     mknodat(int fd, const char	*path, mode_t mode, dev_t dev);

     The file system node path is created with the file	type and access	per-
     missions specified	in mode.  The access permissions are modified by the
     process's umask value.

     If	mode indicates a block or character special file, dev is a configura-
     tion dependent specification denoting a particular	device on the system.
     Otherwise,	dev is ignored.

     The mknod() system	call requires super-user privileges.

     The mknodat() system call is equivalent to	mknod()	except in the case
     where path	specifies a relative path.  In this case the newly created
     device node is created relative to	the directory associated with the file
     descriptor	fd instead of the current working directory.  If mknodat() is
     passed the	special	value AT_FDCWD in the fd parameter, the	current	work-
     ing directory is used and the behavior is identical to a call to mknod().

     The mknod() function returns the value 0 if successful; otherwise the
     value -1 is returned and the global variable errno	is set to indicate the

     The mknod() system	call will fail and the file will be not	created	if:

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

     [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 translat-
			ing the	pathname.

     [EPERM]		The process's effective	user ID	is not super-user.

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

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

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

     [EDQUOT]		The directory in which the entry for the new node 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 user's quota of inodes on the file system on which
			the node is being created has been exhausted.

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

     [EEXIST]		The named file exists.

     [EFAULT]		The path argument points outside the process's allo-
			cated address space.

     [EINVAL]		Creating anything else than a block or character spe-
			cial file (or a	whiteout) is not supported.

     In	addition to the	errors returned	by the mknod(),	the mknodat() may fail

     [EBADF]		The path argument does not specify an absolute path
			and the	fd argument is neither AT_FDCWD	nor a valid
			file descriptor	open for searching.

     [ENOTDIR]		The path argument is not an absolute path and fd is
			neither	AT_FDCWD nor a file descriptor associated with
			a directory.

     chmod(2), mkfifo(2), stat(2), umask(2)

     The mknodat() system call follows The Open	Group Extended API Set 2 spec-

     The mknod() function appeared in Version 6	AT&T UNIX.  The	mknodat() sys-
     tem call appeared in FreeBSD 8.0.

FreeBSD	11.1		       January 16, 2011			  FreeBSD 11.1


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