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mknod(2)		      System Calls Manual		      mknod(2)

NAME
       mknod - make a directory, or a special or ordinary file

SYNOPSIS
       #include	<sys/types.h>
       #include	<sys/stat.h>

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

DESCRIPTION
       mknod()	creates	 a new file named by the path name pointed to by path.
       The file	type and permissions of	the  new  file	are  initialized  from
       mode.

       The  file  type	is specified in	mode by	the S_IFMT bits, which must be
       set to one of the following values:

	  S_IFIFO   fifo special
	  S_IFCHR   character special
	  S_IFDIR   directory
	  S_IFBLK   block special
	  S_IFREG   ordinary file

       The file	access permissions are specified in mode by the	0007777	 bits,
       and may be constructed by an OR of the following	values:

	  S_ISUID   04000   Set	user ID	on execution.
	  S_ISGID   020#0   Set	group ID on execution if # is 7, 5, 3, or 1.
			    Enable mandatory file/record locking if # is 6, 4, 2, or 0.
	  S_ISVTX   01000   Save text image  after execution.
	  S_IRWXU   00700   Read, write, execute by owner.
	  S_IRUSR   00400   Read by owner.
	  S_IWUSR   00200   Write by owner.
	  S_IXUSR   00100   Execute (search if a directory) by owner.
	  S_IRWXG   00070   Read, write, execute by group.
	  S_IRGRP   00040   Read by group.
	  S_IWGRP   00020   Write by group.
	  S_IXGRP   00010   Execute by group.
	  S_IRWXO   00007   Read, write, execute  (search) by others.
	  S_IROTH   00004   Read by others.
	  S_IWOTH   00002   Write by others
	  S_IXOTH   00001   Execute by others.

       The  owner  ID  of  the	file  is  set  to the effective	user ID	of the
       process.	 The group ID of the file is set to the	effective group	ID  of
       the  process.   However,	if the S_ISGID bit is set in the parent	direc-
       tory, then the group ID of the file is inherited	from the  parent.   If
       the  group  ID of the new file does not match the effective group ID or
       one of the supplementary	group IDs, the S_ISGID bit is cleared.

       The access permission 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)).	 If mode indicates a block or  charac-
       ter  special  file, dev is a configuration-dependent specification of a
       character or block I/O device.  If mode does not	indicate a block  spe-
       cial or character special device, dev is	ignored.  See makedev(3C).

       mknod()	may  be	invoked	only by	a privileged user for file types other
       than FIFO special.

       If path is a symbolic link, it is not followed.

RETURN VALUES
       0 is returned upon successful completion; otherwise, -1 is returned and
       errno is	set to indicate	the error.

ERRORS
       mknod()	fails  and creates no new file if one or more of the following
       are true:

       EDQUOT		   The directory where the new	file  entry  is	 being
			   placed  cannot be extended because the user's quota
			   of disk blocks on that file	system	has  been  ex-
			   hausted.

			   The user's quota of inodes on the file system where
			   the file is being created has been exhausted.

       EEXIST		   The named file exists.

       EFAULT		   path	points to an illegal address.

       EINTR		   A signal was	caught during the mknod() function.

       EINVAL		   dev is invalid.

       ELOOP		   Too many symbolic links were	encountered in	trans-
			   lating path.

       EMULTIHOP	   Components  of path require hopping to multiple re-
			   mote	machines and the file system type does not al-
			   low it.

       ENAMETOOLONG	   The length of the path argument exceeds {PATH_MAX},
			   or  the  length  of	a   path   component   exceeds
			   {NAME_MAX} while {_POSIX_NO_TRUNC} is in effect.

       ENOENT		   A component of the path prefix does not exist or is
			   a null pathname.

       ENOLINK		   path	points to a remote machine  and	 the  link  to
			   that	machine	is no longer active.

       ENOSPC		   No space is available.

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

       EPERM		   The	effective  user	 of the	calling	process	is not
			   super-user.

       EROFS		   The directory in which the file is to be created is
			   located on a	read-only file system.

SEE ALSO
       chmod(2), exec(2), mkdir(2), umask(2), makedev(3C), mkfifo(3C), stat(5)

NOTES
       Normally, applications should use the mkdir(2) routine to make a	direc-
       tory, since the function	mknod()	may not	 establish  directory  entries
       for . (the directory itself)
       and  .. (the parent directory), and appropriate permissions are not re-
       quired.	Similarly, mkfifo(3C) should be	used in	preference to  mknod()
       in order	to create FIFOs.

				  14 Apr 1995			      mknod(2)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | NOTES

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