Le 6 juin 07 à 00:04, Jean-Marc Lasgouttes a écrit :
"Mael" == Mael Hilléreau <[EMAIL PROTECTED]> writes:
I am not sure we have evidence that the checksum is costing us too
much.
Mael> Perhaps true for regular files (O(n) complexity), but not really
Mael> for packages(O(n^2) complexity, supposing that there are no
Mael> subdirectories)...
The complexity depends on the total size of the data. A big file is
worse than a small directory.
Of course, but this is not the general case. Also note that this
operation is performed once a second, approximatively.
Mael> But the first question to answer is: do we need it??
I think we do, but I do not remember whiy it is better than our old
time-base version. One advantage is that you detect when a file has
been updated without change: typical of the .aux file written by
LaTeX.
I can trust you but... concerning graphics, identifying this case
isn't really useful: we could just convert each time a modification
arises, which should be detected using the timestamp. In fact, it is
very rare to open a figure into its editor in order to save the file
without changing it!
Mael> Further, if we need it for files, do we need it for directories?
Yes if we want directories to masquerade as files.
Indeed, this seems logic...
It should be possible to feed in order all the bytes of all the files
in the directory to the crc checker. If we have a proper directory
iterator in boost, it should be fairly easy.
This looks like making a tar file, and then computing its CRC.
Mael.
