DataBlade API Programmer's Manual

DataBlade API Programmer's Manual
Chapter 12: DataBlade API Function Descriptions

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mi_lo_read()

The mi_lo_read() function reads a specified number of bytes of data from an open smart large object.

Syntax

#include "milo.h"

...
mi_integer mi_lo_read(conn, LO_fd, buf, nbytes)

		MI_CONNECTION *conn;

		MI_LO_FD LO_fd;

		char *buf;

		mi_integer nbytes; 


conn
is a pointer to the connection descriptor that a previous call to mi_open() or mi_server_connect() established.

LO_fd
is an LO file descriptor for the smart large object from which to read the data. 

buf
is a pointer to a user-allocated character buffer that contains the data that mi_lo_read() reads from the smart large object.

nbytes
is the maximum number of bytes to read from the buf character buffer. This value cannot exceed 2 gigabytes.







 



Valid in Client Application?

Valid in Server Routine?

Yes
Yes

Usage

The mi_lo_read() function reads nbytes of data from the open smart large object that the LO_fd file descriptor identifies. The read begins at the current LO seek position for LO_fd. You can use the mi_lo_tell() function to obtain the current LO seek position.

The function reads this data into the user-allocated buffer that buf references. The buf buffer must be less than 2 gigabytes in size. To read smart large objects that are larger than 2 gigabytes, read them in 2-gigabyte chunks.

To perform a seek operation before a read operation, use the function mi_lo_readwithseek().

Tip: The mi_lo_read() function replaces the mi_large_object_read() function, which Informix supports for backward compatibility only. Use mi_lo_read() for all new DataBlade routines.

Return Values

>=0
The number of bytes that the function has read from the open smart large object to the buf character buffer.

MI_ERROR
The function was not successful.

DataBlade API Programmer's ManualChapter 12: DataBlade API Function Descriptions Home Contents Index Master Index New Book

mi_lo_read()

Syntax

Usage

Return Values >=0 The number of bytes that the function has read from the open smart large object to the buf character buffer. MI_ERROR The function was not successful.

Related Topics

DataBlade API Programmer's Manual
Chapter 12: DataBlade API Function Descriptions

Home Contents Index Master Index New Book

Return Values

>=0
The number of bytes that the function has read from the open smart large object to the buf character buffer.

MI_ERROR
The function was not successful.