The
getttyent(),
and
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.
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 */
#define TTY_IFEXISTS 0x10 /* configured as "onifexists" */
#define TTY_IFCONSOLE 0x20 /* configured as "onifconsole" */
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 */
};
The fields are as follows:
|
| ty_name
|
| |
The name of the character-special file.
|
| ty_getty
|
| |
The name of the command invoked by
init(8)
to initialize tty line characteristics.
|
| ty_type
|
| |
The name of the default terminal type connected to this tty line.
|
| ty_status
|
| |
A mask of bit fields which indicate various actions allowed on this
tty line.
The possible flags are as follows:
|
|
| TTY_ON
|
Enables logins (i.e.,
init(8)
will start the command referenced by
ty_getty
on this entry).
|
| TTY_SECURE
|
Allow users with a uid of 0 to login on this terminal.
|
| TTY_DIALUP
|
Identifies a tty as a dialin line.
If this flag is set, then
isdialuptty()
will return a non-zero value.
|
| TTY_NETWORK
|
| |
Identifies a tty used for network connections.
If this flag is set, then
isnettty()
will return a non-zero value.
|
| TTY_IFEXISTS
|
| |
Identifies a tty that does not necessarily exist.
|
| TTY_IFCONSOLE
|
| |
Identifies a tty that might be a system console.
|
|
| ty_window
|
| |
The command to execute for a window system associated with the line.
|
| 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".
|
| ty_comment
|
| |
Any trailing comment field, with any leading hash marks (``#'') or
whitespace removed.
|
|
If any of the fields pointing to character strings are unspecified,
they are returned as null pointers.
The field
ty_status
will be zero if no flag values are specified.
See
ttys(5)
for a more complete discussion of the meaning and usage of the
fields.
The
getttyent()
function
reads the next line from the ttys file, opening the file if necessary.
The
setttyent()
function
rewinds the file if open, or opens the file if it is unopened.
The
endttyent()
function
closes any open files.
The
getttynam()
function
searches from the beginning of the file until a matching
name
is found
(or until
EOF
is encountered).
