On Thursday 02 December 2010 14:24:51 Andries E. Brouwer wrote: [....] > What one wants to see is the smallest list of changes that change > one tree into the other, the input to a hypothetical version of patch. > Certainly the diff that produces this patch input does not follow > symlinks. > > Another small change I made to my copy of diff is that two regular > files with a length of 0 bytes are not compared. Some programs make > empty files of mode 0 and opening them fails, but the files do not differ. >
Almost a month ago, in a message to bug-diffutils, I described the inverse of this problem: running diff against a non-existing file and an equally named existing file file of zero length resulted in no output. Any real version of patch therefore has no chance to create that file. I repeat my example here: $ diff --version $ diff (GNU diffutils) 3.0 Packaged by Gentoo (3.0) $ mkdir a/c -p $ mkdir b/c -p $ touch b/c/emptyfile $ diff -urN a b http://lists.gnu.org/archive/html/bug-diffutils/2010-11/msg00005.html
