Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!oliveb!amiga!cbmvax!andy
From: andy@cbmvax.UUCP (Andy Finkel)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Supporting the clipboard (Re: Jerry declares the 2000 as 'the most improved computer')
Message-ID: <6357@cbmvax.UUCP>
Date: 21 Mar 89 16:03:56 GMT
References: <8903011852.AA16426@jade.berkeley.edu> <6193@columbia.edu> <10901@well.UUCP> <794@zehntel.UUCP> <10923@well.UUCP> <6206@cbmvax.UUCP> <1989Mar19.023257.20564@ziebmef.uucp>
Reply-To: andy@cbmvax.UUCP (Andy Finkel)
Organization: Commodore Technology, West Chester, PA
Lines: 45

In article <1989Mar19.023257.20564@ziebmef.uucp> cks@ziebmef.UUCP (Chris Siebenmann) writes:
>[hah. finally got around to commenting on this topic.]
>sizes of all sub-things inside it) ... at the beginning of itself. And
>the clipboard.device doesn't appear to support random seeking around
>to write data (when writing to a file, the IFF routines seek back to
>the start of a hunk and write the size once they know it).

You're kidding me, right ?  The CMD_WRITE of the clipboard
device includes an io_Offset field, which you can change
so you can write bytes anywhere in the clip.  You can even
extend the clip (padded with 0s) just by settng the io_Offset
beyond the current clip size.  The docs on CMD_WRITE come
right out and say this, actually.  You are right in that it
doesn't say 'here's how to seek during Write.'  But under
both the READ and WRITE functions, the docs do mention
the autoincrement properties of io_Offset, and how you can
get normal sequential reads/writes by leaving the fields alone.

(I also did an example program for AmigaMail a long time ago.)

If you didn't understand you could have just asked someone.  Time
pressure can get to you sure, but when its so easy to ask the people
who know!

> So (to turn this into a comp.sys.amiga.tech topic), having listened
>to my tale of woe, does anyone have any suggestions? Does the
>clipboard.device support random seeks after all (the documentation is
>remarkably opaque on this point)? Does anyone have a clever idea about
>how to do this, or nifty code?


io_Offset = seek_value;


there you go :-)

-- 
andy finkel		{uunet|rutgers|amiga}!cbmvax!andy
Commodore-Amiga, Inc.

"The salesperson said this computer is the next best thing to sliced
 bread, but didn't say what to do about the crumbs in the disk drive."

Any expressed opinions are mine; but feel free to share.
I disclaim all responsibilities, all shapes, all sizes, all colors.