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skip on direct mode file port

 [1/4] from: anton:lexicon at: 12-Aug-2002 3:02


I run the following code on these two: REBOL/View 1.2.8.3.1 3-Aug-2002 REBOL/View 1.2.1.3.1 21-Jun-2001 fp: open/direct/binary %test-file.r fp: skip fp 4 Now I wait for a long time, while cpu is at maximum. Size of the file is 19 bytes, and it doesn't seem to matter how far I skip to cause the long wait, although skipping 0 returns as expected. What's wrong? Anton.

 [2/4] from: greggirwin::mindspring::com at: 11-Aug-2002 11:38


Hi Anton, << fp: open/direct/binary %test-file.r fp: skip fp 4 Now I wait for a long time, while cpu is at maximum.
>>
I think it's a known issue that SKIP doesn't work on direct/binary files at this point. I thought I had heard that the fix would be in soon, but I haven't seen it yet. I'm willing to wait a bit, assuming they're taking the time to get it really right, because it will open up a lot of new possibilities. --Gregg

 [3/4] from: anton:lexicon at: 12-Aug-2002 16:36


I want to read the last 128 bytes of mpeg audio files. I have fixed up and am fixing up mp3tool.r from the script library, which reads id3v1 tags. Currently, it is reading the whole file into memory, which is wasteful. Is there a way to get the file pointer to the end without reading the whole file? I have a half-solution: Do a buffered read, with the buffer set to 128 bytes, such that the last buffer contents falls over the last 128 bytes. Or could use a larger buffer until the last 128 bytes. Mmm. I don't like it. It's just for fun, so I can wait, too. Anton.

 [4/4] from: gscottjones:mchsi at: 12-Aug-2002 7:49


Hi, Anton, From: "Anton"
> I want to read the last 128 bytes of > mpeg audio files.
<<quoted lines omitted: 12>>
> Mmm. I don't like it. It's just for fun, > so I can wait, too.
This is not the most efficient method, but it does allow skipping within an unbuffered access: my-blk: copy [] fs: size? %license.html fr: open/direct/binary %license.html loop (fs - 178) [copy/part fr 1] loop 178 [append my-blk copy/part fr 1] close fr Hope this helps until skip is repaired for direct/binary. --Scott Jones

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