std::filesystem::path::extension
From cppreference.com
< cpp | filesystem | path
| path extension() const; |
(since C++17) | |
Returns the extension of the filename component of the generic-format view of *this.
If the filename() component of the generic-format path contains a period (.), and is not one of the special filesystem elements dot or dot-dot, then the extension is the substring beginning at the rightmost period (including the period) and until the end of the pathname.
If the first character in the filename is a period, that period is ignored (a filename like ".profile" is not treated as an extension).
If the pathname is either . or .., or if