The mi_lo_read() function

Syntax

mi_integer mi_lo_read(conn, LO_fd, buf, nbytes)
   MI_CONNECTION *conn;
   MI_LO_FD LO_fd;
   char *buf;
   mi_integer nbytes;

conn

This value is one of the following connection values:

A pointer to a connection descriptor established by a previous call to mi_open(), mi_server_connect(), or mi_server_reconnect().

A NULL-valued pointer (database server only)

LO_fd

An LO file descriptor for the smart large object from which to read the data. It is obtained from a previous call to mi_lo_open().

buf

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

nbytes

The maximum number of bytes to read into the buf character buffer. This value cannot exceed 2 GB.

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 GB in size. To read smart large objects that are larger than 2 GB, read them in 2 GB chunks.

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

Return values

>=0

The actual number of bytes that the function has read from the open smart large object to the buf buffer.

MI_ERROR

The function was not successful.