Обсуждение:

hi
I have been trying to use the Postgresql library (libpq.so) and processes in my program.
The scenario is like that:

I have made a small shared library where I wrapp the Postgresql functions.

I then call those library functions (my library) from my program.

The program is to behave as a deamon so it is in a endless while loop.

The program starts by opening a connection to the database, enter the infinite while loop to run some functions.

Inside the while loop it forks many childs which then call one function from the library I made.

After one round the program goes to sleep and wakes up again one minute later.

Now comes the problem:: If I call the same the same functions again, those within the while loop (not the connection call) I get an error return.

It is as if the handle to the connection is not valid any more.

I have checked the program without forking and that works fine.

So my question is what can be done to share a library within processes so they are not duplicating the library includes and so on.

regards

Einar

=?iso-8859-1?Q?Einar_M=E1r_Bj=F6rvinsson?= <emb@media.is> writes:
> The program starts by opening a connection to the database, enter the =
> infinite while loop to run some functions.=20

> Inside the while loop it forks many childs which then call one function =
> from the library I made.

Are you trying to say that you are opening a database connection in the
parent process and passing it down for the children to play around with?
This is a fairly bad idea, unless you have an interlock mechanism to
ensure that only one child uses it at a time.

> It is as if the handle to the connection is not valid any more.=20

Perhaps the child is closing the connection when it's done with it.

            regards, tom lane