Manual Pages  — GETPASS

getpass – get a password

LIBRARY SYNOPSIS DESCRIPTION RETURN VALUES FILES SEE ALSO HISTORY BUGS

Standard C Library (libc, -lc)

#include <pwd.h>

#include <unistd.h>

char *
getpass(const char *prompt);

The getpass() function displays a prompt to, and reads in a password from, /dev/tty. If this file is not accessible, getpass() displays the prompt on the standard error output and reads from the standard input.

The password may be up to _PASSWORD_LEN (currently 128) characters in length. Any additional characters and the terminating newline character are discarded.

The getpass() function turns off character echoing while reading the password.

The getpass() function returns a pointer to the null terminated password.

/dev/tty

A getpass() function appeared in AT&T v7 .

The getpass() function leaves its result in an internal static object and returns a pointer to that object. Subsequent calls to getpass() will modify the same object.

The calling process should zero the password as soon as possible to avoid leaving the cleartext password visible in the process's address space.

Upon receipt of a SIGTSTP, the input buffer will be flushed, so any partially typed password must be retyped when the process continues.