The libecpg library primarily contains
“hidden” functions that are used to implement the
functionality expressed by the embedded SQL commands. But there
are some functions that can usefully be called directly. Note that
this makes your code unportable.
ECPGdebug(int turns on debug
logging if called with the first argument non-zero. Debug logging
is done on on, FILE
*stream)stream. The log contains
all SQL statements with all the input
variables inserted, and the results from the
PostgreSQL server. This can be very
useful when searching for errors in your SQL
statements.
On Windows, if the ecpg libraries and an application are
compiled with different flags, this function call will crash the
application because the internal representation of the
FILE pointers differ. Specifically,
multithreaded/single-threaded, release/debug, and static/dynamic
flags should be the same for the library and all applications using
that library.
ECPGget_PGconn(const char * returns the library database connection handle identified by the given name.
If connection_name)
connection_name is set to NULL, the current
connection handle is returned. If no connection handle can be identified, the function returns
NULL. The returned connection handle can be used to call any other functions
from libpq, if necessary.
It is a bad idea to manipulate database connection handles made from ecpg directly with libpq routines.
ECPGtransactionStatus(const char *
returns the current transaction status of the given connection identified by connection_name)connection_name.
See Section 34.2 and libpq's PQtransactionStatus() for details about the returned status codes.
ECPGstatus(int
returns true if you are connected to a database and false if not.
lineno,
const char* connection_name)connection_name can be NULL
if a single connection is being used.