BIO_s_fd(3)

     BIO_s_fd(3)            0.9.6h (2000-09-17)            BIO_s_fd(3)

     NAME
          BIO_s_fd, BIO_set_fd, BIO_get_fd, BIO_new_fd - file
          descriptor BIO

     SYNOPSIS
           #include <openssl/bio.h>

           BIO_METHOD *   BIO_s_fd(void);

           #define BIO_set_fd(b,fd,c)     BIO_int_ctrl(b,BIO_C_SET_FD,c,fd)
           #define BIO_get_fd(b,c)        BIO_ctrl(b,BIO_C_GET_FD,0,(char *)c)

           BIO *BIO_new_fd(int fd, int close_flag);

     DESCRIPTION
          BIO_s_fd() returns the file descriptor BIO method. This is a
          wrapper round the platforms file descriptor routines such as
          read() and write().

          BIO_read() and BIO_write() read or write the underlying
          descriptor.  BIO_puts() is supported but BIO_gets() is not.

          If the close flag is set then then close() is called on the
          underlying file descriptor when the BIO is freed.

          BIO_reset() attempts to change the file pointer to the start
          of file using lseek(fd, 0, 0).

          BIO_seek() sets the file pointer to position ofs from start
          of file using lseek(fd, ofs, 0).

          BIO_tell() returns the current file position by calling
          lseek(fd, 0, 1).

          BIO_set_fd() sets the file descriptor of BIO b to fd and the
          close flag to c.

          BIO_get_fd() places the file descriptor in c if it is not
          NULL, it also returns the file descriptor. If c is not NULL
          it should be of type (int *).

          BIO_new_fd() returns a file descriptor BIO using fd and
          close_flag.

     NOTES
          The behaviour of BIO_read() and BIO_write() depends on the
          behavior of the platforms read() and write() calls on the
          descriptor. If the underlying file descriptor is in a non
          blocking mode then the BIO will behave in the manner
          described in the BIO_read(3) and BIO_should_retry(3) manual
          pages.

     Page 1                                         (printed 1/19/103)

     BIO_s_fd(3)            0.9.6h (2000-09-17)            BIO_s_fd(3)

          File descriptor BIOs should not be used for socket I/O. Use
          socket BIOs instead.

     RETURN VALUES
          BIO_s_fd() returns the file descriptor BIO method.

          BIO_reset() returns zero for success and -1 if an error
          occurred.  BIO_seek() and BIO_tell() return the current file
          position or -1 is an error occurred. These values reflect
          the underlying lseek() behaviour.

          BIO_set_fd() always returns 1.

          BIO_get_fd() returns the file descriptor or -1 if the BIO
          has not been initialized.

          BIO_new_fd() returns the newly allocated BIO or NULL is an
          error occurred.

     EXAMPLE
          This is a file descriptor BIO version of "Hello World":

           BIO *out;
           out = BIO_new_fd(fileno(stdout), BIO_NOCLOSE);
           BIO_printf(out, "Hello World\n");
           BIO_free(out);

     SEE ALSO
          BIO_seek(3), BIO_tell(3), BIO_reset(3), BIO_read(3),
          BIO_write(3), BIO_puts(3), BIO_gets(3), BIO_printf(3),
          BIO_set_close(3), BIO_get_close(3)

     Page 2                                         (printed 1/19/103)