RevMedia

The LOCK processor. If your routines fall over with an "RTP36 VNAV" message check that you have assigned the file variable and id that you are trying to lock, Remember that a file can be locked using the syntax LOCK filevar.

The LOCK processor has a much extended syntax as documented in RevTech's "Technical Bulletin # 2" by Ron Philips (q.v.). The simplest form of the extended syntax is LOCK filevar,recname,action where action is an alpha code having one of the following values

                    X    Exclusive Lock

                    S    Shared Lock

                    XC   Exclusive Coordinated Lock

                    SC   Shared Coordinated Lock

Note that as these codes should be used as codes NOT as literals ie LOCK WC_SRC_FILE%,ID,XC not LOCK WC_SRC_FILE%,ID,"XC". To cope with this extended syntax, the STATUS() variable has been modded so that in addition to the standard 0s and 1s for successful/unsuccessful locks, there also exists a STATUS() value of 2 meaning that an attempt has been made to use an invalid action code E.g. LOCK WC_SRC_FILE%,ID,SZ.

Mr Philips also documents a further extension of the action code whereby groups within a file can be locked, as can overflow frames.