Problem - Kevin Tafuro

On Windows, you can use the standard EDIT control with ES_PASSWORD specified as a
style flag to mask the characters typed by a user.
Discussion
In the following subsections we’ll look at several different approaches to prompting
for passwords.
Prompting for a password on Unix using getpass( ) or readpassphrase( )
The standard C runtime function getpass( ) is the most portable way to obtain a
password from a user interactively. Unfortunately, it does have several limitations
that you may find unacceptable. The first is that only up to _PASSWORD_LEN (typically
128) characters may be entered; any characters after that are simply discarded. The
second is that the password is stored in a statically defined buffer, so it is not threadsafe,
but ordinarily this is not much of a problem because there is fundamentally no
way to read from the terminal in a thread-safe manner anyway.
The getpass( ) function has the following signature:
#include
#include
char *getpass(const char *prompt);
The text passed as the function’s only argument is displayed on the terminal, terminal
echo is disabled, and input is gathered in a buffer internal to the function until
the user presses Enter. The return value from the function is a pointer to the internal
buffer, which will be at most _PASSWORD_LEN + 1 bytes in size, with the additional
byte left to hold the NULL terminator.
FreeBSD and OpenBSD both support an alternative function, readpassphrase( ), that
provides the underlying implementation for getpass( ). It is more flexible than
getpass( ), allowing the caller to preallocate a buffer to hold a password or passphrase
of any size. In addition, it also supports a variety of control flags that control
its behavior.
The readpassphrase( ) function has the following signature:
#include
#include
char *readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags);
This function has the following arguments:
prompt
String that will be displayed to the user before accepting input.
buf
Buffer into which the input read from the interactive user will be placed.
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