begin Sean Neakums quotation:
> begin Austin Gonyou quotation:
>> No, It does not guarantee. Also, if you're not on the same Inode the
>> file time is different, etc, it's possible to have different md5sums. A
>> basic size and file comparison is probably best for what you want to do.
> The md5sum of a file is based on its contents only. The inode has
> nothing to do with it.
>> Something you can do to test what I'm talking about is copy each of your
>> dumps to another name, binfilexyz.1 or something, then compare it's
>> md5sum against the original. Those should be the only time they match.
> I'm not sure exaclty what you mean by this. The name of the file is
> irrelevant in the computation of the md5sum.
In Emacs' case, there's a niggle with this: if there's already an
emacs-21.1.1 file there, it'll dump as emacs-21.1.2, and the dumped
file will have that version embedded in it. The script I was using to
generate the ms5sum was aware of this, and deleted the dumped files
before each dump, so that the dump always happened to the name
emacs-21.1.1. However, there is a variable, emacs-build-time, which
contains the exact time the dump occurred. So md5sums are no use anyway.
Funnily, the last file dump I did worked correctly at the time, but is
now segfaulting, some hours later.
I was doing the dumps while running three instances of this program,
which I hacked up in a hurry, to generate lots of dirty pages and
actual I/O: http://zork.net/~sneakums/io-test.c
I wonder if the pages that are modified by the dump are not being
written to disk correctly? This last dump was in a D state for a few
minutes while the three io-test instances were running, but it did
complete and seemingly start up correctly a few minutes after I killed
///////////////// | | The spark of a pin
<sneakums@xxxxxxxx> | (require 'gnu) | dropping, falling feather-like.
\\\\\\\\\\\\\\\\\ | | There is too much noise.