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.\" 34.Dd June 4, 1993 35.Dt GETPASS 3 36.Os 37.Sh NAME 38.Nm getpass 39.Nd get a password 40.Sh SYNOPSIS 41.Fd #include <pwd.h> 42.Fd #include <unistd.h> 43.Ft char * 44.Fn getpass "const char *prompt" 45.Sh DESCRIPTION 46The 47.Fn getpass 48function displays a prompt to, and reads in a password from, 49.Pa /dev/tty . 50If this file is not accessible, 51.Fn getpass 52displays the prompt on the standard error output and reads from the standard 53input. 54.Pp 55The password may be up to _PASSWORD_LEN (currently 128) 56characters in length. 57Any additional 58characters and the terminating newline character are discarded. 59.Pp 60The 61.Fn getpass 62function turns off character echoing while reading the password. 63.Pp 64.Sh RETURN VALUES 65The 66.Fn getpass 67function returns a pointer to the null terminated password. 68.Sh FILES 69.Bl -tag -width /dev/tty -compact 70.It Pa /dev/tty 71.El 72.Sh SEE ALSO 73.Xr crypt 3 74.Sh HISTORY 75A 76.Fn getpass 77function appeared in 78.At v7 . 79.Sh BUGS 80The 81.Fn getpass 82function leaves its result in an internal static object and returns 83a pointer to that object. 84Subsequent calls to 85.Fn getpass 86will modify the same object. 87.Pp 88The calling process should zero the password as soon as possible to 89avoid leaving the cleartext password visible in the process's address 90space. 91.Pp 92Upon receipt of a SIGTSTP, the input buffer will be flushed, so any 93partially typed password must be retyped when the process 94continues. 95