https://unix.stackexchange.com/a/247779/44992
While not answering the question posed in the title of the question, it does address a possible cause of the actual problem that the poster was actually trying to solve. Additionally, the other (non-deleted) answers don't answer the question posed in the title either.
I don't mind if my answer is a good candidate for deletion, but I'd like to understand the reasons for it (and also the inconsistency) since both comments on it appear to be by people unable to read beyond the first paragraph, and the other answers address the original question/problem even less than mine does.