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CHFLAGS(2)		       System Calls Manual		      CHFLAGS(2)

NAME
     chflags, lchflags, fchflags -- set file flags

LIBRARY
     Standard C Library (libc, -lc)

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

     int
     chflags(const char *path, u_long flags);

     int
     lchflags(const char *path, int flags);

     int
     fchflags(int fd, u_long flags);

DESCRIPTION
     The file whose name is given by path or referenced by the descriptor fd has
     its flags changed to flags.

     The  lchflags()  system call is like chflags() except in the case where the
     named file is a symbolic link, in which case  lchflags()  will  change  the
     flags of the link itself, rather than the file it points to.

     The flags specified are formed by or'ing the following values

	   UF_NODUMP	 Do not dump the file.
	   UF_IMMUTABLE  The file may not be changed.
	   UF_APPEND	 The file may only be appended to.
	   UF_NOUNLINK	 The file may not be renamed or deleted.
	   UF_OPAQUE	 The  directory  is  opaque  when viewed through a union
			 stack.
	   SF_ARCHIVED	 The file may be archived.
	   SF_IMMUTABLE  The file may not be changed.
	   SF_APPEND	 The file may only be appended to.
	   SF_NOUNLINK	 The file may not be renamed or deleted.
	   SF_SNAPSHOT	 The file is a snapshot file.

     If one of SF_IMMUTABLE, SF_APPEND, or SF_NOUNLINK is set  a  non-super-user
     cannot  change  any  flags and even the super-user can change flags only if
     securelevel is greater than 0.  (See init(8) for details.)

     The UF_IMMUTABLE, UF_APPEND, UF_NOUNLINK, UF_NODUMP,  and	UF_OPAQUE  flags
     may be set or unset by either the owner of a file or the super-user.

     The SF_IMMUTABLE, SF_APPEND, SF_NOUNLINK, and SF_ARCHIVED flags may only be
     set  or unset by the super-user.  Attempts to set these flags by non-super-
     users are rejected, attempts by non-superusers to clear flags that are  al-
     ready  unset are silently ignored.  These flags may be set at any time, but
     normally may only be unset when the system is in  single-user  mode.   (See
     init(8) for details.)

     The  SF_SNAPSHOT  flag is maintained by the system and cannot be changed by
     any user.

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

ERRORS
     The chflags() system call will fail 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]		The named file 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 effective user ID does not match the  owner  of  the
			file and the effective user ID is not the super-user.

     [EPERM]		One  of  SF_IMMUTABLE,	SF_APPEND, or SF_NOUNLINK is set
			and the user is either not the super-user or securelevel
			is greater than 0.

     [EPERM]		A non-super-user  tries  to  set  one  of  SF_IMMUTABLE,
			SF_APPEND, or SF_NOUNLINK.

     [EPERM]		User tries to set or remove the SF_SNAPSHOT flag.

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

     [EFAULT]		The path argument points outside the process's allocated
			address space.

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

     [EOPNOTSUPP]	The underlying file system does not support file flags.

     The fchflags() system call will fail if:

     [EBADF]		The descriptor is not valid.

     [EINVAL]		The fd argument refers to a socket, not to a file.

     [EPERM]		The effective user ID does not match the  owner  of  the
			file and the effective user ID is not the super-user.

     [EPERM]		One  of  SF_IMMUTABLE,	SF_APPEND, or SF_NOUNLINK is set
			and the user is either not the super-user or securelevel
			is greater than 0.

     [EPERM]		A non-super-user  tries  to  set  one  of  SF_IMMUTABLE,
			SF_APPEND, or SF_NOUNLINK.

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

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

     [EOPNOTSUPP]	The underlying file system does not support file flags.

SEE ALSO
     chflags(1), fflagstostr(3), strtofflags(3), init(8), mount_unionfs(8)

HISTORY
     The chflags() and fchflags() system calls first appeared in 4.4BSD.

FreeBSD 7.4			  May 16, 2006			      CHFLAGS(2)
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