1 Version 4.0 -- 5/1/89 dbclropt
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NAME: dbclropt
FUNCTION:
Clear an option set by dbsetopt().
SYNTAX:
RETCODE dbclropt(dbproc, option, param)
DBPROCESS *dbproc;
int option;
char *param;
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COMMENTS:
o This routine clears SQL Server and DB-Library options that have
been set with dbsetopt(). Although SQL Server options may be
set and cleared directly through SQL, the application should
instead use dbsetopt() and dbclropt() to set and clear options.
This provides a uniform interface for setting both SQL Server
and DB-Library options. It also allows the application to use
the dbisopt() function to check the status of an option.
o dbclropt() does not immediately clear the option. The option
is cleared the next time a command buffer is sent to the
SQL Server (by invoking dbsqlexec() or dbsqlsend()).
o For a complete list of options, see the manual page for
options.
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PARAMETERS:
dbproc - A pointer to the DBPROCESS structure that provides the
connection for a particular front end/SQL Server process. It
contains all the information that DB-Library uses to manage
communications and data between the front end and SQL Server.
If dbproc is NULL, the option will be cleared for all active
DBPROCESS structures.
option - The option that is to be turned off. See the options
manual page for the list of options.
param - Certain options take parameters. The DBOFFSET option,
for example, takes as a parameter the SQL construct for which
offsets are to be returned. The options manual page lists
those options that take parameters. If an option does not
take a parameter, param must be NULL.
If the option you are clearing takes a parameter but there
can be only one instance of the option, dbclropt() ignores
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the param argument. For example, dbclropt() ignores the
value of param when clearing the DBBUFFER option, because row
buffering can have only one setting at a time. On the other
hand, the DBOFFSET option can have several settings, each
with a different parameter. It may have been set twice-to
look for offsets to SELECT statements and offsets to ORDER BY
clauses. In that case, dbclropt() needs the param argument
to determine whether to clear the SELECT offset or the ORDER
BY offset. The only other option for which dbclropt()
requires a param is DBSTAT.
If an invalid parameter is specified for one of the
SQL Server options, this will be discovered the next time a
command buffer is sent to the SQL Server. The dbsqlexec() or
dbsqlsend() call will fail, and DB-Library will invoke the
user-installed message handler. If an invalid parameter is
specified for one of the DB-Library options (DBBUFFER or
DBTEXTLIMIT), the dbclropt() call itself will fail.
5 Version 4.0 -- 5/1/89 dbclropt
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RETURNS:
SUCCEED or FAIL.
SEE ALSO:
dbisopt, dbsetopt, options