GETTTYENT(3)                   Library Routines                   GETTTYENT(3)

NAME

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

SYNOPSIS

       #include <ttyent.h>

       struct ttyent *getttyent (void);
       struct ttyent *getttynam (char *name);
       int setttyent (void);
       int endttyent (void);

DESCRIPTION

       The  getttyent, and getttynam functions each return a pointer to an ob‐
       ject, 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 */
            int  ty_status;     /* flag values */
            char *ty_window;    /* command for window manager */
            char *ty_comment;   /* comment field */
       };

       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 al‐
                     lowed on this tty line.  The possible flags are  as  fol‐
                     lows:

                     TTY_ON Enables  logins (i.e., init(8) will start the com‐
                            mand referenced by ty_getty on this entry).

                     TTY_SECURE
                            Allow users with a uid of 0 to login on this  ter‐
                            minal.

              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.

       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 function 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),
       init(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  fu‐
       ture use, it should be copied before any subsequent calls overwrite it.



GNO                            23 February 1996                   GETTTYENT(3)