Обсуждение: asynchronous api questions

Hi,

I have 2 questions regarding the asynchronous C api (I am using vers. 8.4):

1) To make a connection in non-blocking manner the api provides PGconn
*PQconnectStart(const char *conninfo) function. The parameters are
passed in 'conninfo' variable which is a string so I have to use
sprintf() to put the parameters into this string. Is there another
function to connect asynchronously that would be similar to
PQsetdbLogin so it would accept the host/port/user/password parameters
directly as argument to the function? I want to avoid to use sprintf()

2) Will this code produce a valid non-blocking connection ?

    db_globals=PQsetdbLogin(DT_DBHOST,DT_DBPORT,NULL,NULL,"global",DT_DBUSER,DT_DBPASS);
    if (PQstatus(db_globals) != CONNECTION_OK) {
                fprintf(stderr, "Connection to database failed: %s",
                        PQerrorMessage(db_globals));
                PQfinish(db_globals);
                exit(1);
    }
    if (PQsetnonblocking(db_globals, int arg)!=1) {
        printf("can't set global connection to non blocking mode\n");
        exit(1);
    }

Will appreciate any help

Nulik

Nulik Nol wrote:
> I have 2 questions regarding the asynchronous C api (I am using vers.
8.4):
>
> 1) To make a connection in non-blocking manner the api provides PGconn
> *PQconnectStart(const char *conninfo) function. The parameters are
> passed in 'conninfo' variable which is a string so I have to use
> sprintf() to put the parameters into this string. Is there another
> function to connect asynchronously that would be similar to
> PQsetdbLogin so it would accept the host/port/user/password parameters
> directly as argument to the function? I want to avoid to use sprintf()

You can use PQconnectStartParams if you don't want to construct a
conninfo string.

> 2) Will this code produce a valid non-blocking connection ?
>
>
db_globals=PQsetdbLogin(DT_DBHOST,DT_DBPORT,NULL,NULL,"global",DT_DBUSER
,DT_DBPASS);
>     if (PQstatus(db_globals) != CONNECTION_OK) {
>                 fprintf(stderr, "Connection to database failed: %s",
>                         PQerrorMessage(db_globals));
>                 PQfinish(db_globals);
>                 exit(1);
>     }
>     if (PQsetnonblocking(db_globals, int arg)!=1) {
>         printf("can't set global connection to non blocking mode\n");
>         exit(1);
>     }

The resulting connection (db_globals) will not block when you send, but
the
connection procedure itself (PQsetdbLogin) will block.

Yours,
Laurenz Albe