Random acces file updating

methods all advance the file pointer to the next byte, so only one positioning statement is required per record, unless you are reading randomly within the record. Read Bytes(Rec Size) 'No positionng required ' Process the B array Loop '... The processing for that type of file would involve reading a byte at a time, assembling the byte array, until the Eo R marker is detected.Note that, as with any string processing, the actual results will depend on the current encoding.

The first problem with discussing file last-access time is agreeing what you mean by a file's last-access time. Dim Model As String Dim QIS As Double Dim QOO As Double reader. This is a common arrangement for variable length records, and has the advantage the the file pointer is already positioned at the start of the record data after the record length has been read. As a result, many algorithms such as quicksort and binary search degenerate into bad algorithms that are even less efficient than their naive alternatives; these algorithms are impractical without random access.On the other hand, some algorithms, typically those that do not have index, require only sequential access, such as mergesort, and face no penalty.

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