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 val

ues

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.

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

by the nonsuper-user to set the super-user only flags are silently ig

nored. 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.)

RETURN VALUES

The function returns the value 0 if successful; 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 charac

ters.

[ENOENT] The named file does not exist.

[EACCES] Search permission is denied for a compo

nent of the

path prefix.

[ELOOP] Too many symbolic links were encountered

in translat

ing 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.

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

file system.

[EFAULT] The path argument points outside the pro

cess's allo

cated address space.

[EIO] An I/O error occurred while reading from

or writing to

the file system.

[EOPNOTSUPP] The underlying file system does not sup

port 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.

[EROFS] The file resides on a read-only file sys

tem.

[EIO] An I/O error occurred while reading from

or writing to

the file system.

[EOPNOTSUPP] The underlying file system does not sup

port 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.

BSD May 5, 2002

BSD