I am looking some solutions which help me to track any changes which have been made on files. I am working on Linux system where a lot of people have access to the same files. Sometimes it is happened, that someone changed something in file and don't notify other users. So I would like to write some script to check if provide file path or files have been changed, if so then write in file let's say "controlfile_File1.txt" something like that "File changed %date, line XXX". I know that I can use md5checksum for that, but I will get only info if file changed but I would like to know which line is changed. I also think about solution to make copy of this file to some place and make some diff between copied file and current file?
Any ideas? thanks for support.
Your question goes above the possibilities of Linux as a platform: Linux can show you the last modification date of a file, and the last time a file has been accessed (even without modifying the file), but that's it.
What are you are looking for, as already mentioned in the comments, is a version control system. As mentioned indeed, Git is one of them, but there are also others (SourceTree, SourceSafe, Clearcase, ...) each of them having their (dis)advantages.
One thing they all have in common is that modifying such a file does not go that simply anymore: at every time somebody has modified such a file (a file under the version control system), (s)he will be asked why (s)he has done this, this will also be recorded for later reference.