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/*
 * hn.h - interface definition for the HNL
 *
 * Copyright(c) 1988 by Hobart Corporation.
 * Used with permission.
 */

/*
 * port-level declarations
 */
enum hn_bps {HN_1200_BPS, HN_2400_BPS, HN_4800_BPS, HN_9600_BPS};
typedef unsigned hn_bps;

enum hn_parity {HN_P_NONE, HN_P_ODD, HN_P_EVEN};
typedef unsigned hn_parity;

#include <hn_port.h>
typedef struct hn_port hn_port;

#define hn_perror(p) (p->errno)

hn_port *hn_popen(char *dev, hn_bps bps, hn_parity par,
        unsigned data_bits, unsigned stop_bits);
int hn_pclose(hn_port *p);
int hn_pgetc(hn_port *p);
int hn_pputc(int c, hn_port *p);
int hn_pflush(hn_port *p);
int hn_penable(hn_port *p);
int hn_pdisable(hn_port *p);

/*
 * stream-level declarations
 */
enum hn_model {HN_1860, HN_1865, HN_1870, ..., HN_SP1500};
typedef unsigned hn_model;

struct hn_stream
    {
    unsigned si;		/* scale id */
    unsigned fc;		/* function code */
    hn_port *port;		/* attached port */
    char blk_buf[2048];		/* packet buffer */
    int errno;                  /* error code */
    .
    .
    };
typedef struct hn_stream hn_stream;

#define hn_serror(s) (s->errno)

hn_stream *hn_sopen
    (hn_port *p, unsigned si, hn_model m, unsigned fc);
int hn_sclose(hn_stream *s);
int hn_sgetc(hn_stream *s);
int hn_sputc(int c, hn_stream *s);