Strange BlockComment Tag

Hi,

would be great if somebody can explain to me what this tag means:

I see this tag (preceding the filename) from time to time in some sourcecode files, but i have no clue what it is good for.
Its not mentioned in the sun code convention pages at http://java.sun.com/docs/codeconv/html/CodeConventions.doc4.html#216

kind regards
Andy

The '@(#)' prefix comes from the SCCS source code control system code that is used to check in/out source code from a repository. Other source code control systems may use the same prefix. The stuff immediately following the prefix, 'TestFile.java' in your case, is not actually stored in SCCS but is inserted on the fly when you get the file out of SCCS.

Hi Carey,
everything clear now. Thanks for your fast Reply.

Glad somebody could help; I didn't know what @(#) meant. And welcome to the Ranch

What's the purpose? In case I forgot the name of the file I'm editing? Seems a little superfluous to me.

First of all, the '@(#)' was specifically chosen for the C language. It was a pattern that did not appear in normal compiled code, therefore you could scan the binaries for this pattern. Second, the file name usage by itself, like you said, only provided limited usefulness, though it did end up in the binaries in a searchable form. More often the file name was accompanied by the revision number and the date the last modification was checked in.

P.S. The expanded SCCS tags would end up in the binaries by putting them inside string constants. It was pretty cool. You could scan an executable file for the pattern and extract the entire list of files and their versions that went into building it.