67 lines
1.6 KiB
Plaintext
67 lines
1.6 KiB
Plaintext
compile function next_key( Table, TableHandle, Operation, Key )
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begin condition
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pre:
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post:
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end condition
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* this function will return the next available key number for a sequentiall
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* keyed table...It will get a lock and hold it so the calling routine will
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* be responsible for unlocking
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$insert logical
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$insert msg_equates
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declare function msg
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if Operation = 'NEXT' then
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NextRecId = xlate( 'DICT.':Table, '%SK%', 1 , 'X' )
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Locked = false$
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loop
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if rowexists( Table, NextRecId ) then
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NextRecId += 1
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end else
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lock TableHandle, NextRecId then
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Locked = true$
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end else
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NextRecId += 1
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end
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end
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until Locked
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repeat
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return NextRecId
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end else
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open 'DICT.':Table to DictTable else
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MsgInfo = ''
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MsgInfo<mcol$> = -2
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MsgInfo<mrow$> = -2
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MsgInfo<mtext$> = 'Unable to open DICT.':Table:'...'
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Void = msg( '', MsgInfo )
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return 0
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end
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Locked = false$
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loop
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lock DictTable, '%SK%' then
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Locked = true$
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end
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until Locked
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repeat
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NewKey = Key+1
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write NewKey on DictTable, '%SK%' else
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MsgInfo = ''
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MsgInfo<mcol$> = -2
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MsgInfo<mrow$> = -2
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MsgInfo<mtext$> = 'Unable to write ':NewKey:' DICT.':Table:' %SK%...'
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Void = msg( '', MsgInfo )
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return 0
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end
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unlock DictTable, '%SK%' else
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MsgInfo = ''
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MsgInfo<mcol$> = -2
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MsgInfo<mrow$> = -2
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MsgInfo<mtext$> = 'Unable to unlock DICT.':Table:'...'
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Void = msg( '', MsgInfo )
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return 0
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end
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return 0
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end
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