How to transform dos file to unix file?

We know that windoz and unix save files with different endings for each line. If you write a shell script under windoz, it will not work under unix. It may shows ": command not found" on the command line. To solve this problem, we need to change the file format. An easy way to do this is:

$ tr '\r\n' '\n' < dosfile > unixfile

This will replace all the '\r\n' at the end of each line with '\n'.