> One example of this occurred circa 2013-08-30 on the canonical repository for the Fossil DVCS. In that event, file descriptor 2 (standard error) was being erroneously closed (by stunnel, we suspect) prior to sqlite3_open_v2() so that the file descriptor used for the repository database file was 2. Later, an application bug caused an assert() statement to emit an error message by invoking write(2,...). But since file descriptor 2 was now connected to a database file, the error message overwrote part of the database.

Kind of crazy that this is an issue in modern operating systems. There are just so many ways to avoid this obvious footgun of an API design. stdin/out/err should be reserved file descriptors. In fact, why reuse file descriptors at all? Just count up.