getextattr,
lsextattr, rmextattr,
setextattr —
manipulate extended
attributes
getextattr |
[-fhqsx] attrnamespace
attrname filename ... |
lsextattr |
[-fhq] attrnamespace
filename ... |
rmextattr |
[-fhq] attrnamespace
attrname filename ... |
setextattr |
[-fhnq] attrnamespace
attrname attrvalue
filename ... |
setextattr |
-i [-fhnq]
attrnamespace attrname
filename ... |
These utilities are user tools to manipulate the named extended attributes on
files and directories. The attrnamespace argument should
be the namespace of the attribute to retrieve: legal values are
user and system. The
attrname argument should be the name of the attribute,
filename the name of the target file or directory,
attrvalue a string to store in the attribute.
The following options are available:
-f- (Force.) Ignore errors on individual filenames and continue with the
remaining arguments.
-h- (No follow.) If the file is a symbolic link, perform the operation on the
link itself rather than the file that the link points to.
-i- (From stdin.) Read attribute data from stdin instead of as an
argument.
-n- (
NUL-terminate.)
NUL-terminate the extent content written out.
-q- (Quiet.) Do not print out the pathname and suppress error messages. When
given twice, print only the attribute value, with no trailing
newline.
-s- (Stringify.) Escape nonprinting characters and put quotes around the
output.
-x- (Hex.) Print the output in hexadecimal.
setextattr system md5 `md5 -q /boot/kernel/kernel` /boot/kernel/kernel
md5 -q /boot/kernel/kernel | setextattr -i system md5 /boot/kernel/kernel
getextattr system md5 /boot/kernel/kernel
getextattr -qq system md5 /boot/kernel/kernel | od -x
lsextattr system /boot/kernel/kernel
rmextattr system md5 /boot/kernel/kernel
Extended attribute support was developed as part of the TrustedBSD
Project, and introduced in FreeBSD 5.0. It was
developed to support security extensions requiring additional labels to be
associated with each file or directory.
Robert N M Watson
Poul-Henning Kamp