NAME
chflags, fchflags
— set file flags
SYNOPSIS
#include
<sys/stat.h>
#include <unistd.h>
int
chflags(const
char *path, u_int
flags);
int
fchflags(int
fd, u_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 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_OPAQUE
- The directory is opaque when viewed through a union stack.
- UF_HIDDEN
- The file or directory is not intended to be displayed to the user.
- UF_COMPRESSED
- File is compressed at the file system level.
- SF_ARCHIVED
- The file has been archived.
- SF_IMMUTABLE
- The file may not be changed.
- SF_APPEND
- The file may only be appended to.
- SF_DATALESS
- The file is a dataless placeholder. The system will attempt to materialize it when accessed according to the dataless file materialization policy of the accessing thread or process. See getiopolicy_np(3).
The “UF_IMMUTABLE”, “UF_APPEND”, “UF_OPAQUE”, and “UF_HIDDEN” flags may be set or unset by either the owner of a file or the super-user.
The “SF_ARCHIVED”, “SF_IMMUTABLE” and “SF_APPEND” flags may only be set or unset by the super-user.
The “SF_DATALESS” and
“UF_COMPRESSED” flags are internal flags and may not be set or
unset from user space. Attempting to modify them using
chflags()
will result in undefined behaviour.
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 super-user.
- [
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.
- [
ENOTSUP] - The operation isn't supported by the filesystem.
fchflags() will fail if:
- [
EBADF] - The descriptor is not valid.
- [
EINVAL] - fd 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 system.
- [
EIO] - An I/O error occurred while reading from or writing to the file system.
- [
ENOTSUP] - The operation isn't supported by the filesystem.
SEE ALSO
chflags(1), fflagstostr(3), lchflags(3), strtofflags(3), launchd(8)
HISTORY
The chflags() and
fchflags functions first appeared in 4.4BSD.