What does the value 1c1 mean in the diff tool?

Question

I ran diff with two files and got the following output:

1c1
< dbacaad
---
> dbacaad

What does it mean? My two files seem to be exactly the same. Thank you very much!

Answer 1

To answer the question raised in the header: 1c1 indicates that line 1 in the first file was c somehow hung to create line 1 in the second file.

In practical terms: they probably differ in spaces (perhaps trailing spaces or Unix compared to the end of a Windows line?).

diff -w file1 file2, . cmp file1 file2, , .