Dot in file name?

Question

Is it okay to use a "." (dot) in file names instead of camelcase or dashes etc.. for example:

ico_active.user.png

Will it cause any performance or browser compatibility issues or some other disadvantage?

Thanks!

Answer 1

Different OSes have different rules for filenames. For example, filenames cannot consist only of dots. In Windows filenames cannot end with a dot.

There is a convention where file types or formats trail dots; for example a something.tar.gz file is interpreted as the file or folder "something" that has been tar-ed then gzipped.

Dots are also problematic when matching filenames using regular expressions because . is a metacharacter while underscores and letters are not.

Answer 2

If you save the response, then the last part will be used as the file name by some older browsers, but apart from that it's ignored. It used to be fun little joke to play on people to make a URI like ".jpeg" do something interactive because it was really a text/html with some javascript or flash, but these days people are too likely to know how it's done to serve as a prank any more.

IIS does have issues if the period is the final character of the URI, for reasons that escape me.