From: Jonathan Wakely (cow_at_[hidden])
Date: 2005-01-28 05:58:24
On Fri, Jan 28, 2005 at 10:17:54AM +0100, Lars Gullik Bj?nnes wrote:
> Anyway the problem with copy_file is that the requirement on having
> target non-existant is not possible to turn off.
Sounds like there should be a copy_file() overload (or a default
argument) with a "no clobber" flag saying whether or not to overwrite.
This would be analoguous to cp(1)'s -f switch and sh(1)'s >| redirection
operator, which give you the option of clobbering an existing file even
when in safe-by-default mode (i.e. using "cp -i" or "set -o noclobber")
Looking at the implementation of copy_file() I'm wondering why it isn't
done like this (this provides noclobber support too):
// file exists
from_file_ph, to_file_ph, fs::detail::system_error_code() ) );
out << in.rdbuf();
It may not be blindingly fast on all systems (though there's no reason
it can't be, with a good filebuf) but it's a lot simpler than a loop
with read(2)/write(2) and file descriptors that have to be closed
manually, and would work on all platforms.
-- "In times like these, it helps to recall that there have always been times like these." - Paul Harvey
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