[apple/libc.git] / gen / getttyent.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.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 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.
.\"
.\"     @(#)getttyent.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/gen/getttyent.3,v 1.12 2001/10/01 16:08:51 ru Exp $
.\"
.Dd November 17, 1996
.Dt GETTTYENT 3
.Os
.Sh NAME
.Nm getttyent ,
.Nm getttynam ,
.Nm setttyent ,
.Nm endttyent
.Nd get ttys file entry
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In ttyent.h
.Ft struct ttyent *
.Fn getttyent void
.Ft struct ttyent *
.Fn getttynam "const char *name"
.Ft int
.Fn setttyent void
.Ft int
.Fn endttyent void
.Sh DESCRIPTION
The
.Fn getttyent ,
and
.Fn getttynam
functions
each return a pointer to an object, with the following structure,
containing the broken-out fields of a line from the tty description
file.
.Bd -literal
struct ttyent {
	char	*ty_name;	/* terminal device name */
	char	*ty_getty;	/* command to execute, usually getty */
	char	*ty_type;	/* terminal type for termcap */
#define	TTY_ON		0x01	/* enable logins (start ty_getty program) */
#define	TTY_SECURE	0x02	/* allow uid of 0 to login */
#define	TTY_DIALUP	0x04	/* is a dialup tty */
#define	TTY_NETWORK	0x08	/* is a network tty */
	int	ty_status;	/* status flags */
	char	*ty_window;	/* command to start up window manager */
	char	*ty_comment;	/* comment field */
	char	*ty_group;	/* tty group name */
};
.Ed
.Pp
The fields are as follows:
.Bl -tag -width ty_comment
.It Fa ty_name
The name of the character-special file.
.It Fa ty_getty
The name of the command invoked by
.Xr init 8
to initialize tty line characteristics.
.It Fa ty_type
The name of the default terminal type connected to this tty line.
.It Fa ty_status
A mask of bit fields which indicate various actions allowed on this
tty line.
The possible flags are as follows:
.Bl -tag -width TTY_NETWORK
.It Dv TTY_ON
Enables logins (i.e.,
.Xr init 8
will start the command referenced by
.Fa ty_getty
on this entry).
.It Dv TTY_SECURE
Allow users with a uid of 0 to login on this terminal.
.It Dv TTY_DIALUP
Identifies a tty as a dialin line.
.It Dv TTY_NETWORK
Identifies a tty used for network connections.
.El
.It Fa ty_window
The command to execute for a window system associated with the line.
.It Fa ty_group
A group name to which the tty belongs.
If no group is specified in the ttys description file,
then the tty is placed in an anonymous group called "none".
.It Fa ty_comment
Any trailing comment field, with any leading hash marks (``#'') or
whitespace removed.
.El
.Pp
If any of the fields pointing to character strings are unspecified,
they are returned as null pointers.
The field
.Fa ty_status
will be zero if no flag values are specified.
.Pp
See
.Xr ttys 5
for a more complete discussion of the meaning and usage of the
fields.
.Pp
The
.Fn getttyent
function
reads the next line from the ttys file, opening the file if necessary.
The
.Fn setttyent
function
rewinds the file if open, or opens the file if it is unopened.
The
.Fn endttyent
function
closes any open files.
.Pp
The
.Fn getttynam
function
searches from the beginning of the file until a matching
.Fa name
is found
(or until
.Dv EOF
is encountered).
.Sh RETURN VALUES
The routines
.Fn getttyent
and
.Fn getttynam
return a null pointer on
.Dv EOF
or error.
The
.Fn setttyent
function
and
.Fn endttyent
return 0 on failure and 1 on success.
.Sh FILES
.Bl -tag -width /etc/ttys -compact
.It Pa /etc/ttys
.El
.Sh SEE ALSO
.Xr login 1 ,
.Xr ttyslot 3 ,
.Xr gettytab 5 ,
.Xr termcap 5 ,
.Xr ttys 5 ,
.Xr getty 8 ,
.Xr init 8
.Sh HISTORY
The
.Fn getttyent ,
.Fn getttynam ,
.Fn setttyent ,
and
.Fn endttyent
functions appeared in
.Bx 4.3 .
.Sh BUGS
These functions use static data storage;
if the data is needed for future use, it should be
copied before any subsequent calls overwrite it.
Commit	Line	Data
5b2abdfb A	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	.\" @(#)getttyent.3 8.1 (Berkeley) 6/4/93
	33	.\" $FreeBSD: src/lib/libc/gen/getttyent.3,v 1.12 2001/10/01 16:08:51 ru Exp $
	34	.\"
	35	.Dd November 17, 1996
	36	.Dt GETTTYENT 3
	37	.Os
	38	.Sh NAME
	39	.Nm getttyent ,
	40	.Nm getttynam ,
	41	.Nm setttyent ,
	42	.Nm endttyent
	43	.Nd get ttys file entry
5b2abdfb A	44	.Sh LIBRARY
	45	.Lb libc
	46	.Sh SYNOPSIS
	47	.In ttyent.h
	48	.Ft struct ttyent *
	49	.Fn getttyent void
	50	.Ft struct ttyent *
	51	.Fn getttynam "const char *name"
	52	.Ft int
	53	.Fn setttyent void
	54	.Ft int
	55	.Fn endttyent void
5b2abdfb A	56	.Sh DESCRIPTION
	57	The
	58	.Fn getttyent ,
	59	and
	60	.Fn getttynam
	61	functions
	62	each return a pointer to an object, with the following structure,
	63	containing the broken-out fields of a line from the tty description
	64	file.
	65	.Bd -literal
	66	struct ttyent {
	67	char ty_name; / terminal device name */
	68	char ty_getty; / command to execute, usually getty */
	69	char ty_type; / terminal type for termcap */
	70	#define TTY_ON 0x01 /* enable logins (start ty_getty program) */
	71	#define TTY_SECURE 0x02 /* allow uid of 0 to login */
	72	#define TTY_DIALUP 0x04 /* is a dialup tty */
	73	#define TTY_NETWORK 0x08 /* is a network tty */
	74	int ty_status; /* status flags */
	75	char ty_window; / command to start up window manager */
	76	char ty_comment; / comment field */
	77	char ty_group; / tty group name */
	78	};
	79	.Ed
	80	.Pp
	81	The fields are as follows:
	82	.Bl -tag -width ty_comment
	83	.It Fa ty_name
	84	The name of the character-special file.
	85	.It Fa ty_getty
	86	The name of the command invoked by
	87	.Xr init 8
	88	to initialize tty line characteristics.
	89	.It Fa ty_type
	90	The name of the default terminal type connected to this tty line.
	91	.It Fa ty_status
	92	A mask of bit fields which indicate various actions allowed on this
	93	tty line.
	94	The possible flags are as follows:
	95	.Bl -tag -width TTY_NETWORK
	96	.It Dv TTY_ON
	97	Enables logins (i.e.,
	98	.Xr init 8
	99	will start the command referenced by
	100	.Fa ty_getty
	101	on this entry).
	102	.It Dv TTY_SECURE
	103	Allow users with a uid of 0 to login on this terminal.
	104	.It Dv TTY_DIALUP
	105	Identifies a tty as a dialin line.
5b2abdfb A	106	.It Dv TTY_NETWORK
5b2abdfb A	107	Identifies a tty used for network connections.
5b2abdfb A	108	.El
	109	.It Fa ty_window
	110	The command to execute for a window system associated with the line.
	111	.It Fa ty_group
	112	A group name to which the tty belongs.
	113	If no group is specified in the ttys description file,
	114	then the tty is placed in an anonymous group called "none".
	115	.It Fa ty_comment
	116	Any trailing comment field, with any leading hash marks (``#'') or
	117	whitespace removed.
	118	.El
	119	.Pp
	120	If any of the fields pointing to character strings are unspecified,
	121	they are returned as null pointers.
	122	The field
	123	.Fa ty_status
	124	will be zero if no flag values are specified.
	125	.Pp
	126	See
	127	.Xr ttys 5
	128	for a more complete discussion of the meaning and usage of the
	129	fields.
	130	.Pp
	131	The
	132	.Fn getttyent
	133	function
	134	reads the next line from the ttys file, opening the file if necessary.
	135	The
	136	.Fn setttyent
	137	function
	138	rewinds the file if open, or opens the file if it is unopened.
	139	The
	140	.Fn endttyent
	141	function
	142	closes any open files.
	143	.Pp
	144	The
	145	.Fn getttynam
	146	function
	147	searches from the beginning of the file until a matching
	148	.Fa name
	149	is found
	150	(or until
	151	.Dv EOF
	152	is encountered).
	153	.Sh RETURN VALUES
	154	The routines
	155	.Fn getttyent
	156	and
	157	.Fn getttynam
	158	return a null pointer on
	159	.Dv EOF
	160	or error.
	161	The
	162	.Fn setttyent
	163	function
	164	and
	165	.Fn endttyent
	166	return 0 on failure and 1 on success.
5b2abdfb A	167	.Sh FILES
	168	.Bl -tag -width /etc/ttys -compact
	169	.It Pa /etc/ttys
	170	.El
	171	.Sh SEE ALSO
	172	.Xr login 1 ,
	173	.Xr ttyslot 3 ,
	174	.Xr gettytab 5 ,
	175	.Xr termcap 5 ,
	176	.Xr ttys 5 ,
	177	.Xr getty 8 ,
	178	.Xr init 8
	179	.Sh HISTORY
	180	The
	181	.Fn getttyent ,
	182	.Fn getttynam ,
	183	.Fn setttyent ,
	184	and
	185	.Fn endttyent
	186	functions appeared in
	187	.Bx 4.3 .
	188	.Sh BUGS
	189	These functions use static data storage;
	190	if the data is needed for future use, it should be
	191	copied before any subsequent calls overwrite it.