freebsd-dev/lib/libc/gen/getpass.3

.\" Copyright (c) 1989, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)getpass.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
.Dd June 4, 1993
.Dt GETPASS 3
.Os
.Sh NAME
.Nm getpass
.Nd get a password
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In pwd.h
.In unistd.h
.Ft char *
.Fn getpass "const char *prompt"
.Sh DESCRIPTION
The
.Fn getpass
function displays a prompt to, and reads in a password from,
.Pa /dev/tty .
If this file is not accessible,
.Fn getpass
displays the prompt on the standard error output and reads from the standard
input.
.Pp
The password may be up to _PASSWORD_LEN (currently 128)
characters in length.
Any additional
characters and the terminating newline character are discarded.
.Pp
The
.Fn getpass
function turns off character echoing while reading the password.
.Sh RETURN VALUES
The
.Fn getpass
function returns a pointer to the null terminated password.
.Sh FILES
.Bl -tag -width /dev/tty -compact
.It Pa /dev/tty
.El
.Sh SEE ALSO
.Xr crypt 3 ,
.Xr readpassphrase 3
.Sh HISTORY
A
.Fn getpass
function appeared in
.At v7 .
.Sh BUGS
The
.Fn getpass
function leaves its result in an internal static object and returns
a pointer to that object.
Subsequent calls to
.Fn getpass
will modify the same object.
.Pp
The calling process should zero the password as soon as possible to
avoid leaving the cleartext password visible in the process's address
space.
.Pp
Upon receipt of a SIGTSTP, the input buffer will be flushed, so any
partially typed password must be retyped when the process
continues.
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.\" Copyright (c) 1989, 1991, 1993`
			`.\" The Regents of the University of California. All rights reserved.`
			`.\"`
			`.\" Redistribution and use in source and binary forms, with or without`
			`.\" modification, are permitted provided that the following conditions`
			`.\" are met:`
			`.\" 1. Redistributions of source code must retain the above copyright`
			`.\" notice, this list of conditions and the following disclaimer.`
			`.\" 2. Redistributions in binary form must reproduce the above copyright`
			`.\" notice, this list of conditions and the following disclaimer in the`
			`.\" documentation and/or other materials provided with the distribution.`
			`.\" 4. Neither the name of the University nor the names of its contributors`
			`.\" may be used to endorse or promote products derived from this software`
			`.\" without specific prior written permission.`
			`.\"`
			.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
			`.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE`
			`.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE`
			`.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE`
			`.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL`
			`.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS`
			`.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)`
			`.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT`
			`.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY`
			`.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF`
			`.\" SUCH DAMAGE.`
			`.\"`
			`.\" @(#)getpass.3 8.1 (Berkeley) 6/4/93`
$Id$ -> $FreeBSD$ 1999-08-28 00:22:10 +00:00			`.\" $FreeBSD$`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.\"`
			`.Dd June 4, 1993`
			`.Dt GETPASS 3`
			`.Os`
			`.Sh NAME`
			`.Nm getpass`
			`.Nd get a password`
Introduce ".Lb" macro to libc manpages. More libraries manpages updates following. 2000-04-21 09:42:15 +00:00			`.Sh LIBRARY`
			`.Lb libc`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh SYNOPSIS`
mdoc(7) police: Use the new .In macro for #include statements. 2001-10-01 16:09:29 +00:00			`.In pwd.h`
			`.In unistd.h`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Ft char *`
			`.Fn getpass "const char *prompt"`
			`.Sh DESCRIPTION`
			`The`
			`.Fn getpass`
			`function displays a prompt to, and reads in a password from,`
			`.Pa /dev/tty .`
			`If this file is not accessible,`
Update a bunch of man pages to use .Fn instead of .Nm when referencing funciton names. 1996-08-22 22:05:59 +00:00			`.Fn getpass`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`displays the prompt on the standard error output and reads from the standard`
			`input.`
			`.Pp`
			`The password may be up to _PASSWORD_LEN (currently 128)`
			`characters in length.`
			`Any additional`
			`characters and the terminating newline character are discarded.`
			`.Pp`
Update a bunch of man pages to use .Fn instead of .Nm when referencing funciton names. 1996-08-22 22:05:59 +00:00			`The`
			`.Fn getpass`
			`function turns off character echoing while reading the password.`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh RETURN VALUES`
Update a bunch of man pages to use .Fn instead of .Nm when referencing funciton names. 1996-08-22 22:05:59 +00:00			`The`
			`.Fn getpass`
			`function returns a pointer to the null terminated password.`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh FILES`
Fixed various problems: typos, grammer, missing include files wrong function type declarations, and wrong argument type declarations. 1996-05-23 01:05:25 +00:00			`.Bl -tag -width /dev/tty -compact`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.It Pa /dev/tty`
			`.El`
			`.Sh SEE ALSO`
mdoc(7) police: add missing comma. 2001-11-22 09:48:54 +00:00			`.Xr crypt 3 ,`
Introduce readpassphrase(3), a superset of getpass(3). This comes originally from Todd Miller. Obtained from: OpenBSD 2001-11-20 15:15:42 +00:00			`.Xr readpassphrase 3`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh HISTORY`
			`A`
Update a bunch of man pages to use .Fn instead of .Nm when referencing funciton names. 1996-08-22 22:05:59 +00:00			`.Fn getpass`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`function appeared in`
			`.At v7 .`
			`.Sh BUGS`
			`The`
Update a bunch of man pages to use .Fn instead of .Nm when referencing funciton names. 1996-08-22 22:05:59 +00:00			`.Fn getpass`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`function leaves its result in an internal static object and returns`
			`a pointer to that object.`
			`Subsequent calls to`
Update a bunch of man pages to use .Fn instead of .Nm when referencing funciton names. 1996-08-22 22:05:59 +00:00			`.Fn getpass`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`will modify the same object.`
			`.Pp`
			`The calling process should zero the password as soon as possible to`
			`avoid leaving the cleartext password visible in the process's address`
			`space.`
Finally complete my fix for the behaviour of getpass(3) upon receipt of signals. Signals are now properly caught, tty state is being restored, and the previous sigaction triggered. Upon receipt of a sigcont, echo is turned off again. SIGTSTP causes a buffer flush, the man page mentions this. (Although i rather think of it as a feature than a bug.) This is likely to be my last FreeBSD action for 1995, xearth shows me that our .au guys must already write 1996. :-) 1995-12-31 14:00:25 +00:00			`.Pp`
			`Upon receipt of a SIGTSTP, the input buffer will be flushed, so any`
			`partially typed password must be retyped when the process`
			`continues.`