CHFLAGS(2)

NAME
chflags, fchflags - set file flags

SYNOPSIS
#include <sys/stat.h>
#include <unistd.h>
int
chflags(const char *path, unsigned int flags);
int
fchflags(int fd, unsigned int flags);

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

The flags are the bitwise OR of zero or more of 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.
SF_ARCHIVED
    The file may be archived.
SF_IMMUTABLE
    The file may not be changed.
SF_APPEND
    The file may only be appended to.

The UF_IMMUTABLE and UF_APPEND flags may be set or unset by either the owner of a file or the superuser.

The SF_ARCHIVED, SF_IMMUTABLE and SF_APPEND flags may only be set or unset by the superuser. They 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
Upon successful completion, a value of 0 is returned. Otherwise, -1 is returned and the global variable errno is set to indicate the error.

ERRORS
chflags() will fail if:

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

[ENAMETOOLONG]
    A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} 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 superuser, or the effective user ID is not the superuser and at least one of the super-user-only flags for the named file would be changed.

[EOPNOTSUPP]
    The named file resides on a file system that does not support file flags.

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

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

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

[EINVAL]
    The flags value is invalid.

[EINVAL]
    The descriptor references a block or character device and the effective user ID is not the superuser.

fchflags() will fail if:

[EBADF]
    The descriptor is not valid.

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

[EINVAL]
    The descriptor references a block or character device and the effective user ID is not the superuser.

[EINVAL]
    The flags value is invalid.

[EPERM]
    The effective user ID does not match the owner of the file and the effective user ID is not the superuser, or the effective user ID is not the superuser and at least one of the super-user-only flags for the named file would be changed.

[EOPNOTSUPP]
    The named file resides on a file system that does not support file flags.

[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.

SEE ALSO
chflags(1), init(8)

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