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What I'm trying to do is input file1 if it exists and input file2 otherwise, without having to deal with an 'I can't find file' error. I would like to accomplish this using TeX, without using symbolic links. What I would like is some kind of
Of course, this would try to input file1 and, if it encounters an error, input file2 instead.
I'm sure people who are more proficient than I am with plain TeX could accomplish this easily.
(Please feel free to edit the tags.)