49 lines
1.6 KiB
C
49 lines
1.6 KiB
C
/* $Header$ */
|
|
/* channel.h - channel definitions */
|
|
#include <stdio.h>
|
|
#include "parco.h"
|
|
|
|
typedef union channel {
|
|
struct { /* Interprocess channel */
|
|
char _type; /* Channel type, see note */
|
|
char synch; /* State in channel synchronization */
|
|
long val; /* Transmitted value */
|
|
} c;
|
|
struct { /* File channel */
|
|
char _type; /* Dummy field, see note */
|
|
char index; /* Index in the file array */
|
|
char flgs; /* Status flags: in use & readahead */
|
|
char preread; /* Possible preread character */
|
|
} f;
|
|
} chan;
|
|
#define type c._type /* Channel type */
|
|
/* Note: The channel type should not be part of each structure in chan. But
|
|
* the C alignment rules would make chan about 50% bigger if we had done it
|
|
* the right way. Note that the order of fields in a struct cannot be a problem
|
|
* as long as struct c is the largest within the union.
|
|
*/
|
|
|
|
#define C_T_CHAN 0 /* Type of a interprocess channel */
|
|
#define C_T_FILE 1 /* Type of a file channel */
|
|
|
|
#define C_S_FREE 0 /* IP channel is free */
|
|
#define C_S_ANY 1 /* IP channel contains data */
|
|
#define C_S_ACK 2 /* IP channel data is removed */
|
|
|
|
#define C_F_EOF (-1L) /* File channel returns EOF */
|
|
#define C_F_TEXT (-2L) /* File channel becomes line oriented */
|
|
#define C_F_RAW (-3L) /* File channel becomes character oriented */
|
|
|
|
#define C_F_INUSE 0x01 /* File channel is connected to a UNIX file */
|
|
#define C_F_READAHEAD 0x02 /* File channel has a preread character */
|
|
|
|
extern chan file[_NFILE]; /* Array of file channels */
|
|
extern FILE *unix_file[_NFILE]; /* Pointers to buffered UNIX files */
|
|
|
|
void c_init();
|
|
|
|
void chan_in(), cbyte_in(), c_wa_in(), c_ba_in();
|
|
void chan_out(), c_wa_out(), c_ba_out();
|
|
|
|
int chan_any();
|