int mmap_full_file(const char *filename, int open_mode, void **map,
size_t *size, int *fd_ptr);
int para_munmap(void *start, size_t length);
+int read_ok(int fd);
int write_ok(int fd);
void valid_fd_012(void);
-int readv_nonblock(int fd, struct iovec *iov, int iovcnt, fd_set *rfds,
- size_t *num_bytes);
-int read_nonblock(int fd, void *buf, size_t sz, fd_set *rfds, size_t *num_bytes);
-int read_pattern(int fd, const char *pattern, size_t bufsize, fd_set *rfds);
+int readv_nonblock(int fd, struct iovec *iov, int iovcnt, size_t *num_bytes);
+int read_nonblock(int fd, void *buf, size_t sz, size_t *num_bytes);
+int read_pattern(int fd, const char *pattern, size_t bufsize);
int xwrite(int fd, const char *buf, size_t len);
int xwritev(int fd, struct iovec *iov, int iovcnt);
int for_each_file_in_dir(const char *dirname,