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. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)getpass.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD$ 34.\" 35.Dd June 4, 1993 36.Dt GETPASS 3 37.Os 38.Sh NAME 39.Nm getpass 40.Nd get a password 41.Sh SYNOPSIS 42.Fd #include <pwd.h> 43.Fd #include <unistd.h> 44.Ft char * 45.Fn getpass "const char *prompt" 46.Sh DESCRIPTION 47The 48.Fn getpass 49function displays a prompt to, and reads in a password from, 50.Pa /dev/tty . 51If this file is not accessible, 52.Fn getpass 53displays the prompt on the standard error output and reads from the standard 54input. 55.Pp 56The password may be up to _PASSWORD_LEN (currently 128) 57characters in length. 58Any additional 59characters and the terminating newline character are discarded. 60.Pp 61The 62.Fn getpass 63function turns off character echoing while reading the password. 64.Pp 65.Sh RETURN VALUES 66The 67.Fn getpass 68function returns a pointer to the null terminated password. 69.Sh FILES 70.Bl -tag -width /dev/tty -compact 71.It Pa /dev/tty 72.El 73.Sh SEE ALSO 74.Xr crypt 3 75.Sh HISTORY 76A 77.Fn getpass 78function appeared in 79.At v7 . 80.Sh BUGS 81The 82.Fn getpass 83function leaves its result in an internal static object and returns 84a pointer to that object. 85Subsequent calls to 86.Fn getpass 87will modify the same object. 88.Pp 89The calling process should zero the password as soon as possible to 90avoid leaving the cleartext password visible in the process's address 91space. 92.Pp 93Upon receipt of a SIGTSTP, the input buffer will be flushed, so any 94partially typed password must be retyped when the process 95continues. 96