Applying the patch command using files in different directories in Linux

Question

I'm trying to apply a patch using 2 files in different directories. The output file should be in a different directory too. The first file is in /var/local/documents/document.xml and patch file is located in /var/local/patches/patch.diff and I want the output file should be created in /var/local/final/final.xml.

When the files are located in the same directory, this command works:

patch document.xml -i patch.diff -o final.xml

But when they are in separate directories and I try to use the following command:

patch /var/local/documents/document.xml -i /var/local/patches/patch.diff -o /var/local/final/final.xml

I get the following error:

(Stripping trailing CRs from patch.)
patching file {file}
Hunk#1 FAILED at 20.
1 out of 1 hunk FAILED -- saving rejects to file {file}

I've read somewhere that I should use -d and -p to work correctly with directories but I have no clue how I should do it...

Answer 1

Yes, it's -p switch (in your case it should strip 2 entries from patch path):

cd /var/local/documents
patch -p 2 -o ../final/final.xml document.xml < ../patches/patch.diff

Answer 2

Try this:

$ mv /var/local/final/final.xml /var/local/final/document.xml
$ (cd /var/local/final && patch document.xml) < patch.diff
$ mv /var/local/final/document.xml /var/local/final/final.xml