| EXTATTRCTL(8) | System Manager's Manual | EXTATTRCTL(8) | 
extattrctl —
| extattrctl | startpath | 
| extattrctl | stoppath | 
| extattrctl | initattr[-f]
      [-ppath]
      attrsize attrfile | 
| extattrctl | showattrattrfile | 
| extattrctl | enablepath
      attrnamespace attrname
      attrfile | 
| extattrctl | disablepath
      attrnamespace attrname | 
extattrctl utility is the management utility for
  extended attributes over the UFS1 file system. It allows the starting and
  stopping of extended attributes on a file system, as well as initialization of
  attribute backing files, and enabling and disabling of specific extended
  attributes on a file system.
The first argument on the command line indicates the operation to be performed. Operation must be one of the following:
start
    pathUFS_EXTATTR kernel option must have been
      enabled. If .attribute/user and
      .attribute/system exist at the filesystem root,
      extended attributes backed by files in these directories will be
      automatically enabled. Note that extended attributes can be automatically
      started at mount time by using the -o extattr
      option to mount(8).stop
    pathinitattr
    [-f] [-p
    path] attrsize attrfileThe -f argument may be used to
        indicate that it is alright to overwrite an existing attribute backing
        file; otherwise, if the target file exists, an error will be
      returned.
The -p path
        argument may be used to preallocate space for all attributes rather than
        relying on sparse files to conserve space. This has the advantage of
        guaranteeing that space will be available for attributes when they are
        written, preventing low disk space conditions from denying attribute
        service.
This file should not exist before running
        initattr.
When a user attempts to set a “user” or “system” extended attribute that lacks a backing file, the kernel will attempt to automatically create it, provided .attribute/user or .attribute/system exist and are writable by the requesting user.
showattr
    attrfileenable
    path attrnamespace attrname attrfileinitattr before its
      first use. Attributes must have been started on the file system prior to
      the enabling of any attributes.disable
    path attrnamespace attrnameenable.extattrctl start /Start extended attributes on the root file system.
extattrctl initattr 17
  /.attribute/system/md5Create an attribute backing file in /.attribute/system/md5, and set the maximum size of each attribute to 17 bytes, with a sparse file used for storing the attributes.
extattrctl enable / system md5
  /.attribute/system/md5Enable an attribute named md5 on the root file system, backed from the file /.attribute/system/md5.
extattrctl disable / md5Disable the attribute named md5 on the root file system.
extattrctl stop /Stop extended attributes on the root file system.
extattrctl works only on UFS1 file systems. The kernel
  support for extended attribute backing files and this control program should
  be generalized for any file system that lacks native extended attribute
  support.
| June 17, 2011 | NetBSD 9.4 |