Solaris due to not flushing the input buffer.
This change also incorporates some additional getpass implementation
suggestions for security based on an analysis of getpass.c linked to from the
issue.
* Default to using /dev/tty for the password prompt and input before
falling back to sys.stdin and sys.stderr.
* Use sys.stderr instead of sys.stdout.
* print the 'password may be echoed' warning to stream used to display
the prompt rather than always sys.stderr.
* warn() with GetPassWarning when input may be echoed.
Make sure we have a UNIX-compatible termios.
Apparently, McMillan Installer made a termios on windows
which caused unix_getpass() to be used instead of win_getpass().
Will backport.
At import time, getpass will be bound to the appropriate
platform-specific function. If the platform's echo-disabler is not
available, default_getpass, which prints the warning, will be used
Windows. If sys.stdin doesn't appear to be a real file (characterized
by having a working fileno()), don't use any console specific methods
-- go straight to the default.
the tty and the caller can deal with the interrupt.
In the windows version, recognize ^C and raise KeyboardInterrupt (not
sure if this is needed, but can't hurt).
