1.\" Copyright (c) 1989, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)getpass.3 8.1 (Berkeley) 6/4/93 29.\" $FreeBSD$ 30.\" 31.Dd June 4, 1993 32.Dt GETPASS 3 33.Os 34.Sh NAME 35.Nm getpass 36.Nd get a password 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In pwd.h 41.In unistd.h 42.Ft char * 43.Fn getpass "const char *prompt" 44.Sh DESCRIPTION 45The 46.Fn getpass 47function displays a prompt to, and reads in a password from, 48.Pa /dev/tty . 49If this file is not accessible, 50.Fn getpass 51displays the prompt on the standard error output and reads from the standard 52input. 53.Pp 54The password may be up to _PASSWORD_LEN (currently 128) 55characters in length. 56Any additional 57characters and the terminating newline character are discarded. 58.Pp 59The 60.Fn getpass 61function turns off character echoing while reading the password. 62.Sh RETURN VALUES 63The 64.Fn getpass 65function returns a pointer to the null terminated password. 66.Sh FILES 67.Bl -tag -width /dev/tty -compact 68.It Pa /dev/tty 69.El 70.Sh SEE ALSO 71.Xr crypt 3 , 72.Xr readpassphrase 3 73.Sh HISTORY 74A 75.Fn getpass 76function appeared in 77.At v7 . 78.Sh BUGS 79The 80.Fn getpass 81function leaves its result in an internal static object and returns 82a pointer to that object. 83Subsequent calls to 84.Fn getpass 85will modify the same object. 86.Pp 87The calling process should zero the password as soon as possible to 88avoid leaving the cleartext password visible in the process's address 89space. 90.Pp 91Upon receipt of a SIGTSTP, the input buffer will be flushed, so any 92partially typed password must be retyped when the process 93continues. 94