Re: Suggestions for FIlEMAN.E
>Like Dbase, how about a status byte as the first character in a record?
>To represent a deleted record, place an ASCII 0 there, and an ASCII 1 or
>larger code to represent a valid, active record. Thus, when you
>delete a record, all you need to do is set the status byte to zero. You
>can leave the actual record data alone, which will permit an undelete
>later, if you desire.
So long as the data hasn't been overwritten by another record, at least..
>One record format I read about placed an ASCII 26 after the header
>identification. ASCII 26 is the old end of file marker for DOS.
>Thus, if you placed such a character at byte position
>3, then if the file is read in line mode, by Euphoria or another program,
>all they will see is Eu.
I've seen this done. For example, in the game, Command & Conquer, you saved
the games by typing in a description, ie, "GDI defending base - About to
win!". The file would be saved like SAVEGAME.004. The first few characters
of the file is the entire description, with a EOF (ASCII 26) marker at like
the 50th position. So, in DOS, "TYPE SAVEGAME.010" would give you the
description of that saved game, and nothing else. I thought this was cool...
>I think Ralf mentioned that you should open these files in binary mode.
>That way any character from 0 to 255 is permissable and will not affect
>the read or write routines.
Correct. Binary is what should usually be used, unless actually dealing with
text files.
>It might be fun to code a routine to compact the file in place.
>That is, you could rearrange the file such that all deleted records
>are placed after all the data records, without coping to a second file.
Or purging all the deleted records....
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