This chapter explains how you can develop your own C application using the libraries and tools supplied by the LIXA project.
The LIXA project ships with some example C programs that you can find in the /opt/lixa/share/doc/lixa-X.Y.Z/examples folder after software installation (see Chapter 2, Installation).
This chapter is focused on the C programming language for the non-standard extensions that has been added to the TX specification to expose some of the XA interface capabilities. All the information supplied in Chapter 5, Developing C Application Programs using TX (Transaction Demarcation) interface still applies.
The LIXA project provides extensions to the [TXspec], named Transaction Coupling (TC) [40], which can be used in addition to the standard API when developing distributed Application Programs.
The API extensions are easy to use and the following C example briefly explains it:
#include <tx.h>
/* your includes */
int main(int argc, char *argv[])
{
int rc;
if (TX_OK != (rc = tx_open()))
/* handle error */
if (TX_OK != (rc = tx_begin()))
/* handle error */
/* do local work against Resource Manager here */
/* suspend the transaction so that work can continue elsewhere */
if (TX_OK != (rc = tx_end(TX_TMSUSPEND)))
/* handle error */
/* in another thread or another Application Program work can continue on the same transaction */
TXINFO txinfo;
if (TX_OK != (rc = tx_info(&txinfo)))
/* handle error */
if (TX_OK != (rc = tx_join(&txinfo.xid)))
/* handle error */
if (TX_OK != (rc = tx_end(TX_TMSUCCESS)))
/* handle error */
/* take up transaction again */
if (TX_OK != (rc = tx_resume(&txinfo.xid)))
/* handle error */
/* commit or roll back transaction */
if (TX_OK != (rc = tx_commit()))
/* handle errror */
/* shut down */
tx_close();
}
These are the available C functions:
tx_end: manage the global transaction with flags:
TX_TMSUSPEND: suspend the transaction
TX_TMSUCCESS: mark the portion of work on the global transaction as successful
TX_TMFAIL: mark the portion of work on the global transaction as failed
tx_join: join a suspended global transaction and continue work
tx_resume: resume a suspended global transaction - only from the thread that suspended the original transaction