set_extension

Description:

public bool set_extension (string extension)

Adds an extension to the file name in the path buffer.

If extension is `NULL`, the extension will be unset.

If the path buffer does not have a file name set, this function returns `FALSE` and leaves the path buffer unmodified.

this	a path buffer
extension	the file extension

`TRUE` if the extension was replaced, and `FALSE` otherwise