#include /* BASIC file io definitions */ extern FILE *_chanrd; extern FILE *_chanwr; extern int _chann; /* BASIC file descriptor table */ /* Channel assignment: -1 terminal IO 0 data file 1-15 user files */ /* FILE MODES:*/ #define IMODE 1 #define OMODE 2 #define RMODE 3 typedef struct { char *fname; FILE *fd; int pos; int mode; int reclength; }Filedesc; extern Filedesc _fdtable[16];