Transaction control in a C language function

Hello all,

I would like to implement transaction control in a function implemented in C language. Currently I'm using SPI to do the job.

When calling SPI_commit() it returns this error message:

SQL Error [XX000]: ERROR: portal snapshots (0) did not account for all active snapshots (1)

Below, there is an example.

PG_FUNCTION_INFO_V1(my_commit);

Datum my_commit(PG_FUNCTION_ARGS)
{
    SPIExecuteOptions execopts;

    SPI_connect_ext(SPI_OPT_NONATOMIC);

    memset(&execopts, 0, sizeof(execopts));
    execopts.params = NULL;
    execopts.read_only = false;
    execopts.allow_nonatomic = true;
    execopts.must_return_tuples = false;
    execopts.tcount = 0;
    execopts.dest = NULL;
    execopts.owner = NULL;

    /* Execute some SQL commands */
    SPI_execute_extended("UPDATE mytable SET name = 'done'", &execopts);

    /* Commit the transaction */
    SPI_commit();

    SPI_finish();

    PG_RETURN_NULL();
}

Thanks in advance,

Flaris Feller