#ifndef _RIO_H_
#define _RIO_H_

/* Persistent state for the robust I/O (Rio) package */
#define RIO_BUFSIZE 8192

typedef struct {
  int rio_fd;                /* Descriptor for this internal buf */
  int rio_cnt;               /* Unread bytes in internal buf */
  char *rio_bufptr;          /* Next unread byte in internal buf */
  char rio_buf[RIO_BUFSIZE]; /* Internal buffer */
} rio_t;

/* Rio (Robust I/O) package */
ssize_t rio_readn(int fd, void *usrbuf, size_t n);
ssize_t rio_writen(int fd, const void *usrbuf, size_t n);
void rio_readinitb(rio_t *rp, int fd);
ssize_t rio_readnb(rio_t *rp, void *usrbuf, size_t n);
ssize_t rio_readlineb(rio_t *rp, void *usrbuf, size_t maxlen);

/* Wrappers that exit on failure */
ssize_t Rio_readn(int fd, void *ptr, size_t nbytes);
void Rio_writen(int fd, const void *usrbuf, size_t n);
ssize_t Rio_readnb(rio_t *rp, void *usrbuf, size_t n);
ssize_t Rio_readlineb(rio_t *rp, void *usrbuf, size_t maxlen);

#endif /* !_RIO_H_ */