Whenever the password is needed, a seek() and read() can be performed to obtain it. Do *not* close the file descriptor until it is known the password is never required again.

No other user can open this file since it has no read or write permissions. Secondly, it will only exist on the file system for an extremely short period of time. If it were created in a directory with excessively restricted permissions then only root would ever be able to get to it.

If your program dumps core, the .mypassword file will not be available since it has already been unlinked. Not until the last file descriptor is closed will the space be reclaimed. As far as I know, this is true of all unix file systems, not sure how it works with Windows. If you are concerned about core dumps, then I think Windows is irrelevant.

For the majority of the runtime, all the core dump will contain is evidence of a file descriptor, which gives away zero information.

For the remainder of the runtime, there is a slight chance a core dump might contain the password. This could be eliminated if the authentication mechanism allowed for passwords to be sent byte at a time, but I have never seen such a system.

Alternatively, rotating the passwords might avoid this problem too.

-Frank