application do that.

NOTE: there's no requirement for other UI_METHODs to avoid this kind
of loop.  For example, a GUI UI_METHOD would probably check the
lengths of the answers from within instead of being constantly
redisplayed for everything that is wrong.

prompting, application-defined prompts, the possibility to use
defaults (for example default passwords from somewhere else) and
interrupts/cancelations.

In the new crypto/ui/, this was changed into tty (which is usually
/dev/tty), i.e. the FILE * used for reading passwords from the user.
However stdio buffering for read/write streams is not without pitfalls
(passwords would be echoed on some systems).
To avoid problems, split tty into tty_in and tty_out (which are
opened separately).

For some unknown reason fopen("con", "w") is the
only way to make this work. Using "r+" and "w+"
causes the fopen call to fail and the fallback
(using stdin) doesn't work because writing to stdin
fails.

(basically: whooops :-))

little bit clearer and use the new OPENSSL_SYS_* macros.

like des_read_password and friends (backward compatibility functions
using this new API are provided).  The purpose is to remove prompting
functions from the DES code section as well as provide for prompting
through dialog boxes in a window system and the like.