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GETTTYENT(3)             BSD Library Functions Manual             GETTTYENT(3)

NAME
     getttyent, getttynam, setttyent, 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
     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, 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 */
     };

     The fields are as follows:

     ty_name     The name of the character-special file.

     ty_getty    The name of the command invoked 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

                 TTY_SECURE   Allow users with a uid of 0 to login on this terminal.

                 TTY_DIALUP   Identifies a tty as a dialin line.

                 TTY_NETWORK  Identifies a tty used for network connections.

     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).

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

FILES
     /etc/ttys

SEE ALSO
     login(1), ttyslot(3), gettytab(5), termcap(5), ttys(5), getty(8),

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

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.

BSD                            November 17, 1996                           BSD