Kai Gro�johann:
I got several bug reports about rcp.el failing to see that a target
file wasn't writable. What do you think is the best approach?
(1) Check whether copy/rename will succeed, first. Barf if not, else
do it.
(2) Just do stuff, but check for errors in each step.
(3) Check first, then check again after each step.
For (1), would it be sufficient to do the following? Check that the
source file exists and is readable. If the target file already
exists, check that it is writable. If the target file doesn't exist,
check that the target directory is writable.
Or do we also want to check for available disk space and stuff?
Your last question means that 1) is not enough. Lots of things can go
wrong while writing a file, so checks after each step are always
required. This leads to 2). I think going to 3) is not necessary.
