.\" Copyright (c) 1989 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)chflags.2	6.4 (Berkeley) %G%
.\"
.Dd 
.Dt CHFALGS 2
.Os BSD 4.4
.Sh NAME
.Nm chflags ,
.Nm fchflags
.Nd set file flags
.Sh SYNOPSIS
.Fd #include <unistd.h>
.Ft int
.Fn chflags "const char *path"  "long flags"
.Ft int
.Fn fchflags "int fd" "long flags"
.Sh DESCRIPTION
The file whose name
is given by
.Fa path
or referenced by the descriptor
.Fa fd
has its flags changed to
.Fa flags .
.Pp
Only the owner of a file (or the super-user) may change the flags.
The owner may only change the lower 16 bits of the flags;
the super-user may change all 32 bits of the flags.
.Sh RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, -1 is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
.Fn Chflags
fails if:
.Bl -tag -width Er
.It Bq Er ENOTDIR
A component of the path prefix is not a directory.
.It Bq Er EINVAL
The pathname contains a character with the high-order bit set.
.It Bq Er ENAMETOOLONG
A component of a pathname exceeded 255 characters,
or an entire path name exceeded 1023 characters.
.It Bq Er ENOENT
The named file does not exist.
.It Bq Er EACCES
Search permission is denied for a component of the path prefix.
.It Bq Er ELOOP
Too many symbolic links were encountered in translating the pathname.
.It Bq Er EPERM
The effective user ID does not match the owner of the file and
the effective user ID is not the super-user.
.It Bq Er EROFS
The named file resides on a read-only file system.
.It Bq Er EFAULT
.Fa Path
points outside the process's allocated address space.
.It Bq Er EIO
An I/O error occurred while reading from or writing to the file system.
.El
.Pp
.Fn Fchflags
will fail if:
.Bl -tag -width Er
.It Bq Er EBADF
The descriptor is not valid.
.It Bq Er EINVAL
.Fa Fd
refers to a socket, not to a file.
.It Bq Er EPERM
The effective user ID does not match the owner of the file and
the effective user ID is not the super-user.
.It Bq Er EROFS
The file resides on a read-only file system.
.It Bq Er EIO
An I/O error occurred while reading from or writing to the file system.
.El
.Sh SEE ALSO
.Xr chmod 2 ,
.Xr open 2 ,
.Xr chown 2 ,
.Xr stat 2
.Sh HISTORY
The
.Nm
function call is currently under development.