/* tty.h */

#define TY_OBMINSP      20              /* Min space in buffer before   */
                                        /*   processes awakened to write*/
#define TY_EBUFLEN      20              /* Size of echo queue           */

/* Size constants */

#ifndef Ntty
#define Ntty            1               /* Number of serial tty lines   */
#endif
#ifndef TY_IBUFLEN
#define TY_IBUFLEN      128             /* Num. chars in input queue    */
#endif
#ifndef TY_OBUFLEN
#define TY_OBUFLEN      64              /* Num. chars in output queue   */
#endif

/* Mode constants for input and output modes */

#define TY_IMRAW        'R'             /* Raw input mode => no edits   */
#define TY_IMCOOKED     'C'             /* Cooked mode => line editing  */
#define TY_IMCBREAK     'K'             /* Honor echo, etc, no line edit*/
#define TY_OMRAW        'R'             /* Raw output mode => no edits  */

struct  ttycblk {                       /* Tty line control block       */
        char    *tyihead;               /* Next input char to read      */
        char    *tyitail;               /* Next slot for arriving char  */
        char    tyibuff[TY_IBUFLEN];    /* Input buffer (holds one line)*/
        sid32   tyisem;                 /* Input semaphore              */
        char    *tyohead;               /* Next output char to xmit     */
        char    *tyotail;               /* Next slot for outgoing char  */
        char    tyobuff[TY_OBUFLEN];    /* Output buffer                */
        sid32   tyosem;                 /* Output semaphore             */
        char    *tyehead;               /* Next echo char to xmit       */
        char    *tyetail;               /* Next slot to deposit echo ch */
        char    tyebuff[TY_EBUFLEN];    /* Echo buffer                  */
        char    tyimode;                /* Input mode raw/cbreak/cooked */
        bool8   tyiecho;                /* Is input echoed?             */
        bool8   tyieback;               /* Do erasing backspace on echo?*/
        bool8   tyevis;                 /* Echo control chars as ^X ?   */
        bool8   tyecrlf;                /* Echo CR-LF for newline?      */
        bool8   tyicrlf;                /* Map '\r' to '\n' on input?   */
        bool8   tyierase;               /* Honor erase character?       */
        char    tyierasec;              /* Primary erase character      */
        char    tyierasec2;             /* Alternate erase character    */
        bool8   tyeof;                  /* Honor EOF character?         */
        char    tyeofch;                /* EOF character (usually ^D)   */
        bool8   tyikill;                /* Honor line kill character?   */
        char    tyikillc;               /* Line kill character          */
        int32   tyicursor;              /* Current cursor position      */
        bool8   tyoflow;                /* Honor ostop/ostart?          */
        bool8   tyoheld;                /* Output currently being held? */
        char    tyostop;                /* Character that stops output  */
        char    tyostart;               /* Character that starts output */
        bool8   tyocrlf;                /* Output CR/LF for LF ?        */
        char    tyifullc;               /* Char to send when input full */
};
extern  struct  ttycblk ttytab[];

/* Characters with meaning to the tty driver */

#define TY_BACKSP       '\b'            /* Backspace character          */
#define TY_BACKSP2      '\177'          /* Alternate backspace char.    */
#define TY_BELL         '\07'           /* Character for audible beep   */
#define TY_EOFCH        '\04'           /* Control-D is EOF on input    */
#define TY_BLANK        ' '             /* Blank                        */
#define TY_NEWLINE      '\n'            /* Newline == line feed         */
#define TY_RETURN       '\r'            /* Carriage return character    */
#define TY_STOPCH       '\023'          /* Control-S stops output       */
#define TY_STRTCH       '\021'          /* Control-Q restarts output    */
#define TY_KILLCH       '\025'          /* Control-U is line kill       */
#define TY_UPARROW      '^'             /* Used for control chars (^X)  */
#define TY_FULLCH       TY_BELL         /* Char to echo when buffer full*/

/* Tty control function codes */

#define TC_NEXTC        3               /* Look ahead 1 character       */
#define TC_MODER        4               /* Set input mode to raw        */
#define TC_MODEC        5               /* Set input mode to cooked     */
#define TC_MODEK        6               /* Set input mode to cbreak     */
#define TC_ICHARS       8               /* Return number of input chars */
#define TC_ECHO         9               /* Turn on echo                 */
#define TC_NOECHO       10              /* Turn off echo                */