h5testFileLocking false negatives - fails in a directory without permissions

[LTLA]

dir.create("things")

library(rhdf5)
B = array(seq(0.1,2.0,by=0.1),dim=c(5,2,2))
attr(B, "scale") <- "liter"
h5write(B, "things/stuff.h5","B")

Sys.chmod(paths="things/", mode="544")

# Everything works fine with file locking
h5ls("things/stuff.h5")
h5read("things/stuff.h5", "B") 

# But yet...
h5testFileLocking("things/")
## [1] FALSE
## Warning message:
## In file.remove(file) :
##   cannot remove file 'things//filed7661b820f0d', reason 'No such file or directory'

The most obvious problem is that there is an extraneous warning when the file cannot be created. The less obvious problem is that file locking still seems to work when we don't have write access to the file, in which case rhdf5's check is not quite correct. Perhaps a better solution would be to test the file locking capability on a file-by-file basis prior to read operations.