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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.\" @(#)getttyent.3 8.1 (Berkeley) 6/4/93 29.\" $FreeBSD: src/lib/libc/gen/getttyent.3,v 1.15 2007/01/09 00:27:54 imp Exp $ 30.\" 31.Dd September 20, 2023 32.Dt GETTTYENT 3 33.Os 34.Sh NAME 35.Nm getttyent , 36.Nm getttynam , 37.Nm setttyent , 38.Nm endttyent , 39.Nm isdialuptty , 40.Nm isnettty 41.Nd 42.Xr ttys 5 43file routines 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 56.Ft int 57.Fn isdialuptty "const char *name" 58.Ft int 59.Fn isnettty "const char *name" 60.Sh DESCRIPTION 61The 62.Fn getttyent , 63and 64.Fn getttynam 65functions 66each return a pointer to an object, with the following structure, 67containing the broken-out fields of a line from the tty description 68file. 69.Bd -literal 70struct ttyent { 71 char *ty_name; /* terminal device name */ 72 char *ty_getty; /* command to execute, usually getty */ 73 char *ty_type; /* terminal type for termcap */ 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 81The fields are as follows: 82.Bl -tag -width ".Fa ty_comment" 83.It Fa ty_name 84The name of the character-special file. 85.It Fa ty_getty 86The name of the command invoked by 87.Xr init 8 88to initialize tty line characteristics. 89.It Fa ty_type 90The name of the default terminal type connected to this tty line. 91.It Fa ty_status 92A mask of bit fields which indicate various actions allowed on this 93tty line. 94The possible flags are as follows: 95.Bl -tag -width ".Dv TTY_IFCONSOLE" 96.It Dv TTY_ON 97Enables logins (i.e., 98.Xr init 8 99will start the command referenced by 100.Fa ty_getty 101on this entry). 102.It Dv TTY_SECURE 103Allow users with a uid of 0 to login on this terminal. 104.It Dv TTY_DIALUP 105Identifies a tty as a dialin line. 106If this flag is set, then 107.Fn isdialuptty 108will return a non-zero value. 109.It Dv TTY_NETWORK 110Identifies a tty used for network connections. 111If this flag is set, then 112.Fn isnettty 113will return a non-zero value. 114.It TTY_IFCONSOLE 115Only enables a tty if it's the console. 116.It TTY_IFEXISTS 117Only enables a tty if it exists. 118.El 119.It Fa ty_window 120The command to execute for a window system associated with the line. 121.It Fa ty_group 122A group name to which the tty belongs. 123If no group is specified in the ttys description file, 124then the tty is placed in an anonymous group called 125.Dq none . 126.It Fa ty_comment 127Any trailing comment field, with any leading hash marks 128.Pq # 129or whitespace removed. 130.El 131.Pp 132If any of the fields pointing to character strings are unspecified, 133they are returned as null pointers. 134The field 135.Fa ty_status 136will be zero if no flag values are specified. 137.Pp 138See 139.Xr ttys 5 140for a more complete discussion of the meaning and usage of the 141fields. 142.Pp 143The 144.Fn getttyent 145function 146reads the next line from the ttys file, opening the file if necessary. 147The 148.Fn setttyent 149function 150rewinds the file if open, or opens the file if it is unopened. 151The 152.Fn endttyent 153function 154closes any open files. 155.Pp 156The 157.Fn getttynam 158function 159searches from the beginning of the file until a matching 160.Fa name 161is found 162(or until 163.Dv EOF 164is encountered). 165.Sh RETURN VALUES 166The routines 167.Fn getttyent 168and 169.Fn getttynam 170return a null pointer on 171.Dv EOF 172or error. 173The 174.Fn setttyent 175function 176and 177.Fn endttyent 178return 0 on failure and 1 on success. 179.Pp 180The routines 181.Fn isdialuptty 182and 183.Fn isnettty 184return non-zero if the dialup or network flag is set for the 185tty entry relating to the tty named by the argument, and 186zero otherwise. 187.Sh FILES 188.Bl -tag -width ".Pa /etc/ttys" -compact 189.It Pa /etc/ttys 190.El 191.Sh SEE ALSO 192.Xr login 1 , 193.Xr gettytab 5 , 194.Xr termcap 5 , 195.Xr ttys 5 , 196.Xr getty 8 , 197.Xr init 8 198.Sh HISTORY 199The 200.Fn getttyent , 201.Fn getttynam , 202.Fn setttyent , 203and 204.Fn endttyent 205functions appeared in 206.Bx 4.3 . 207.Sh BUGS 208These functions use static data storage; 209if the data is needed for future use, it should be 210copied before any subsequent calls overwrite it. 211