Creating a file with timestamp 4782

No, I mean what I said ("open" is a libc function, and it will succeed unless you use OEXCL).

That's not a log. It's a dump. You can generate cores with the pid as part of the name easy enough.

Then why not generate a core? Anyway, it doesn't matter. What you want to do (generate a unique filename) is trivial, hence, if you can't do it, by implication, you can't do a mound of other trivial things too, like "program". Programmingf consists of looking in the manual for components that might be useful for your purposes and combining them to obtain the desired effect. You've failed to do that. There are mounds of functions in the manual for generating unique file names, and generic file locking would enable you to generate a unique file name on your own.

What difference does the language it is written in make?

An "application" is a program, any user program. I don't know what you mean. Perhaps you are confusing a compiled program with an interpreted program? Anyway, it makes no difference. "Application" implies only that it is not part of the system, but has a defined extra-system objective, such as "counting parking tickets".

They tried. They failed.

Peter