=== XATTR_ flag combinations
dumb_setxattr -p /mnt/test/test/simple-xattr-unit/file -n user.test -v val -c -r
returned -1 errno 22 (Invalid argument)
dumb_setxattr -p /mnt/test/test/simple-xattr-unit/file -n user.test -v val -r
returned -1 errno 61 (No data available)
dumb_setxattr -p /mnt/test/test/simple-xattr-unit/file -n user.test -v val -c
returned 0
dumb_setxattr -p /mnt/test/test/simple-xattr-unit/file -n user.test -v val -c
returned -1 errno 17 (File exists)
dumb_setxattr -p /mnt/test/test/simple-xattr-unit/file -n user.test -v val -r
returned 0
=== bad lengths
setfattr: /mnt/test/test/simple-xattr-unit/file: Operation not supported
setfattr: /mnt/test/test/simple-xattr-unit/file: Numerical result out of range
setfattr: /mnt/test/test/simple-xattr-unit/file: Numerical result out of range
setfattr: /mnt/test/test/simple-xattr-unit/file: Argument list too long
=== good length boundaries
=== 500 random lengths
=== alternate val size between interesting sizes