The mi_stream_read() function
The mi_stream_read() function reads a specified number of bytes from a stream into a buffer.
Syntax
mi_integer mi_stream_read(strm_desc, buf, nbytes)
MI_STREAM *strm_desc;
void *buf;
mi_integer nbytes;- strm_desc
- A pointer to a stream descriptor for an open stream.
- buf
- A pointer to a user-allocated buffer.
- nbytes
- The maximum number of bytes to read into the buf buffer.
| Valid in client LIBMI application? | Valid in user-defined routine? |
|---|---|
| No | Yes |
Usage
The mi_stream_read() function reads up to nbytes bytes from the open stream that strm_desc references. The function copies this data into the buf user-defined buffer. The read operation begins at the current stream seek position. You can use mi_stream_tell() or mi_stream_getpos() to obtain this seek position.
To read to the end of the stream,
call mi_stream_read() in a loop until it returns
the MI_STREAM_EEOF constant, as follows:
- For all calls except the last call, mi_stream_read() reads nbytes or fewer bytes and returns the number of bytes it has read.
- For the last call, mi_stream_read() returns the MI_STREAM_EEOF constant to indicate that it has reached the end of the stream without any errors.
Return values
- >=0
- The number of bytes that the function has read from the open stream
to the buf buffer.
The number of bytes read might be less than the nbytes value.
- MI_STREAM_EEOF
- The end of the stream has been reached without any errors.
- MI_STREAM_EBADARG
- The stream descriptor that strm_desc references is invalid, the buf user-defined buffer is invalid, or the specified nbytes value is less than zero.
- MI_STREAM_ENIMPL
- The stream class does not implement the stream-read function.
- MI_ERROR
- The function was not successful.