TipcConnGetGmdMaxSize

Name

TipcConnGetGmdMaxSize — get the maximum size of a connection’s GMD area

Synopsis

T_BOOL TipcConnGetGmdMaxSize(conn, gmd_max_size_return) 
T_IPC_CONN conn; 
T_UINT4 *gmd_max_size_return;

Arguments

conn — connection to get GMD area maximum size from

gmd_max_size_return — storage for connection GMD area maximum size

Return Values

TRUE if the GMD area maximum size was successfully retrieved from the connection, FALSE otherwise.

Diagnostics

If TipcConnGetGmdMaxSize fails, it returns FALSE and sets the global SmartSockets error number to one of:

T_ERR_NULL_PTR — conn was null or gmd_max_size_return was null

T_ERR_VAL_INVALID — the connection is not set up for GMD. TipcConnGmdFileCreate must be called before TipcConnGetGmdMaxSize.

Description

TipcConnGetGmdMaxSize gets the GMD area maximum size (in bytes) of a connection. A GMD area holds guaranteed message delivery information for both incoming and outgoing messages. There are two types of guaranteed message delivery: file-based GMD and memory-only GMD. See TipcConnGmdFileCreate for more information on GMD areas.

For file-based GMD, this limit is the maximum file size, and for memory-only GMD this limit is the maximum amount of memory allowed. The default GMD area maximum size is 0, which means that no GMD area maximum size limit checking is performed. The connection GMD area maximum size and the connection delivery timeout can be used to constrain the amount of system resources used for GMD by space and by time.

If the connection GMD area maximum size is exceeded, then no further messages can be sent with guaranteed delivery (TipcConnMsgSend returns FALSE and sets the global SmartSockets error number to T_ERR_VAL_TOO_LARGE) until some unacknowledged previously sent messages are acknowledged.

Caution

If TipcConnGetGmdMaxSize returns FALSE, it does not store a value in gmd_max_size_return.

Examples

This example prints the GMD area maximum size of a connection:

T_UINT4 gmd_max_size; 
 
if (!TipcConnGetGmdMaxSize(conn, &gmd_max_size)) { 
  return;  /* error */ 
}  
 
TutOut("Connection GMD max size is %d.\n", gmd_max_size);