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   D_RBLCLR

SUMMARY
   d_rblclr([dbn])
   int dbn;

ARGUMENTS
   dbn         (optional)The number of the database containing the record

DESCRIPTION
   Function d_rlbclr is called to clear the record lock bit of the current
   record. After a record occurrene is locked, the record will remain locked
   until function d_rblcr is called to clear the lock bit.If d_rldclr is
   called from within a transaction ,the data file which contains the current
   record must be write-locked.User error S_NOTLOCKED is returned if the
   function is called within atransaction and the datafile of a current record
   is not write-locked.The clearing of record lock bit cannot be applied until
   the transaction ends because other modifications to be to the record are
   unusually involved in the transaction.If d_trabort is called after d_rlbclr,
   the clear is aborted and the record remains lockod.The lock bit is clear
   througth the cache rather than directly to the file when d_rldclr is called
   within a transaction.If d_rlbclr is called outside of a transaction, the
   file does not need to be locked and the operation will directly clear the
   lock bit on the file.This is used to clear the lock bit on the file.This is
   used to clear alock after it has been determined that the record no
   longer needs to update.

   The db_VISTA runtime does not provide any automatic protection against
   charged to records that have the lock bit set.Itis the responsibility of
   the application program to ensure that the record lock bit is first
   checked before updating a record.

   No records have which have been locked by the program should remain
   locked after the database is closed.The Database Consistency utility,
   dbcheck, cande used to report all record occurrences which have the
   lock bit set.

   This function is present in the single user version of db_VISTA, but
   performs no action.This allows multi-user applications to link with the
   single user version for operation on stand-alone computer.

------------------------------------------------------------------------------

CURRENCY CHANGES
   None.

RETURN CODES

    -7      S_NOCR       The cuurent record is null.

    -24     S_NOTLOCKED  Current record's file is not write-locked.

EXAMPLE
    /*fetch record to be modified*/
    ...
    if(d_rblset()!=S_OKEY)
    /* unable to access record*/
     ...
    else{
     /*display record and allow user to edit it*/
     ...
     d_trbegin("mod");
     while(d_reclock(REC,"w")==S_UNAVAIL)
        ;/*wait for file's become available */
     d_recwrite(&rec); /*update record*/
     d_rlbclr();       /*unlock record*/
     d_trend();        /*end transaction*/
    }

See Also: d_rlbset d_rlbtst

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