Obtain data as a null-terminated string

This function performs the following steps:

1. Allocates a new buffer to hold the null-terminated string
   Server only: The mi_lvarchar_to_string() function allocates the string that it creates with the current memory duration.
2. Copies the data in the data portion of the varying-length structure to the newly allocated buffer

   The mi_lvarchar_to_string() function automatically copies the number of bytes that the data length in the varying-length descriptor specifies. It then appends a null terminator to the string.

3. Returns a pointer to the newly allocated null-terminated string

Suppose you have the varying-length structure that Figure 1 shows. The following code fragment uses the mi_lvarchar_to_string() function to obtain this varying-length data as a null-terminated string:

mi_lvarchar *lvarch;
char *var_str;
...
var_str = mi_lvarchar_to_string(lvarch);

The code fragment does not need to allocate memory for the var_str string because the mi_lvarchar_to_string() function allocates memory for the new string. After the call to mi_lvarchar_to_string() completes successfully, the var_str variable contains the following null-terminated string:

A varying-length structure stores data in a data portion, which is separate 
from the varying-length structure.