Updated: 2022/Sep/29

Please read Privacy Policy. It's for your privacy.


GETTTYENT(3)               Library Functions Manual               GETTTYENT(3)

NAME
     getttyent, getttynam, setttyent, setttyentpath, endttyent - get ttys file
     entry

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ttyent.h>

     struct ttyent *
     getttyent(void);

     struct ttyent *
     getttynam(const char *name);

     int
     setttyent(void);

     int
     setttyentpath(const char *path);

     int
     endttyent(void);

DESCRIPTION
     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 */
             char    *ty_type;       /* terminal type */
     #define TTY_ON          0x01    /* enable logins */
     #define TTY_SECURE      0x02    /* allow uid of 0 to login */
     #define TTY_LOCAL       0x04    /* set 'CLOCAL' on open (dev. specific) */
     #define TTY_RTSCTS      0x08    /* set 'CRTSCTS' on open (dev. specific) */
     #define TTY_SOFTCAR     0x10    /* ignore hardware carrier (dev. spec.) */
     #define TTY_MDMBUF      0x20    /* set 'MDMBUF' on open (dev. specific) */
     #define TTY_DTRCTS      0x40    /* set 'CDTRCTS' on open (dev. specific) */
             int     ty_status;      /* flag values */
             char    *ty_window;     /* command for window manager */
             char    *ty_comment;    /* comment field */
             char    *ty_class;      /* category of tty usage */
     };

     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_LOCAL    If the terminal port's driver supports it, cause
                              the line to be treated as ``local.''

                 TTY_MDMBUF   If the terminal port's driver supports it, use
                              DTR/DCD hardware flow control on the line by
                              default.

                 TTY_RTSCTS   If the terminal port's driver supports it, use
                              full-duplex RTS/CTS hardware flow control on the
                              line by default.

                 TTY_SOFTCAR  If the terminal port's driver supports it,
                              ignore hardware carrier on the line.

     ty_window   The command to execute for a window system associated with
                 the line.

     ty_comment  Any trailing comment field, with any leading hash marks
                 (``#'') or whitespace removed.

     ty_class    A key indexing into a capfile style database
                 (/etc/ttyclasses) of attributes for this class of tty.  No
                 attributes are currently defined or used, so there are
                 currently no functions to retrieve them.

     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 setttyentpath() function
     is equivalent to setttyent() but accepts an additional argument to read
     the ttys information from an alternate file instead of the default
     location (defined in _PATH_TTYS).  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).

RETURN VALUES
     The routines getttyent() and getttynam() return a null pointer on EOF or
     error.  The setttyent() and setttyentpath() functions and endttyent()
     return 0 on failure and 1 on success.

FILES
     /etc/ttys

SEE ALSO
     login(1), ttyslot(3), capfile(5), gettytab(5), ttys(5), getty(8),
     init(8), ttyflags(8)

HISTORY
     The getttyent(), getttynam(), setttyent(), and endttyent() functions
     appeared in 4.3BSD.  The setttyentpath() function appeared in NetBSD 4.0.

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.

NetBSD 10.99                   February 7, 2014                   NetBSD 10.99