Greetings.

On Monday, September 6, 2004, at 08:26  AM, BrucesFB3@... wrote:

> Hello All,
>
> Given the code below:
>
> I understand this has something to do with opening files by
> double clicking icons in the Finder.
>
> I have been able to use the functions successfully. Everything
> works.
>
> My problem is that I don't know why it works. Obviously,
> FN FBWDToFSSpec() is checking for a particular type of error.
> What kind of error? What is the trigger?

I believe that it is checking that the file/folder exists in this 
case...if it does, no error will occur.

Often times one has to make an FSSpec for a file that doesn't exist 
yet, so you'll get a -43 File Not Found error returned. In this case it 
seems that it wants to verify that it does exist already, so if there's 
noErr, then all is fine.

>
> Also in FN FBWDToFSSpec(), what are the purposes of
> FN FBWDToPBWD( pb ) and FN PBGetCatInfoSync( pb).
> What is the CInfoPBRec?

> FN FBWDToPBWD( pb )

That makes a "classic" type of Param block situation work in Carbon, 
the main difference being that in classic, a vRefnum is often a Working 
Directory Reference number (folder number basically, an open one that 
the system gives you)... and not a real volume reference number.

In Carbon however, you need to use true vRefNums, which in OS X are 
numbered -100,-200, -300 etc...for the volumes mounted. And also the 
Directory ID's need to be sync'ed up or filled in too. FB does a lot of 
this transparently using the FN FBWDToPBWD( pb ) convention, 
automatically refinancing a WD into a VRefnum and doing any DirID work 
too (I believe)

You only need that in Carbon. It insures that the PB calls will return 
valid results in carbon so you don't go writing to the North Pole when 
you want the South, or just get stuck at the equator with no results.

>
> What is the meaning of the syntax, AS .Str63? (period before Str63).

That means Pointer to String 63

Say you have   dim 63 myText$

You can pass that as @myText$[1]   or often simply, @myText$

Where that is going to will have it incoming as a string pointer.

Things like DrawText will want the former. Byte [0] is the length byte. 
But FB will convert a string to a pointer as you go along, often don't 
need to worry about it, as you can see in that code..only gFile$ is 
passed in fn readFile$ , not @gFile$.

Might be off on a couple, but hopefully I am not filling your head with 
gunk. :)

rc


>
> Bruce Gottshall
>
> ====================
> In the file handling code
> ====================
>
> Clear Local Mode
> Local Fn FBWDToFSSpec(@namePtr As .Str63, vRefNum As Int,fSpec As 
> .FSSpec)
> Dim err As OSErr
> Dim pb   As CInfoPBRec
> '~'<
> pb.ioNamePtr = namePtr
> pb.ioVRefNum = vRefNum
> #If CarbonLib
> Fn FBWDToPBWD( pb )
> #Endif
> err = Fn PBGetCatInfoSync( pb )
> If err != _noErr Then Exit Fn
> fSpec.name     =   namePtr.nil$
> fSpec.vRefNum =   pb.ioVRefNum
> fSpec.parID    =   pb.ioFlParID
> End Fn = err
> '~'4
> '==============================
> clear local
> dim theErr as OSErr
> dim AppFolderRef as long
> '~'1
> local fn readFile$
> AppFolderRef = system(_aplVol)
> theErr=fn FBMakeFSSpec(AppFolderRef,0,"",dataFileSpec)
> '-------------------------------------------------
> long if fn FBMakeFSSpec(AppFolderRef,0,"",dataFileSpec) = _noErr
> '-------------------------------------------------
> long if gFound
> xelse
> gFile$ = FILES$ (_FSSpecOpen,"ZDAT","Open which?...", dataFileSpec)
> gFound=_ztrue
> end if
> '-------------------------------------------------
> long if len(gFile$)                    // if not CANCELled
> long if Fn FBWDToFSSpec( gFile$, gVolRefNum, dataFileSpec ) = _noErr or
> gFound
> open "I",#1,@dataFileSpec
> '------------------------------------------------
> FOR j=0 TO gNI
> READ #1, gDate$(J);8, gItem$(J);44, gComm$(J);44
> READ #1, gChNum$(J);12, gAmt$(J);12
> NEXT j
> '------------------------------------------------
> CLOSE #1
> end if
> end if
> end if
> end fn = gFile$
>
> =================================
> In MAIN
> =================================
>
> clear local
> dim @ count, fileName as str31, fType as long, vRefNum, j
> dim action
> '~'<
> local fn MyFinderInfo
> count = 0
> action = finderinfo (count, fileName, fType, vRefNum)
> long if ( count > 0 )                    // at least one file wants in
> for j = -1 to -count step -1        // process them all
> action = finderinfo (j, fileName, fType, vRefNum)
> long if ( action == _finderInfoOpen )
> gFound=_ztrue
> gFile$=fileName
> gVolRefNum=vRefNum
> fn readFile$
> xelse
> end if
> next j
> fn ClearFinderInfo
> end if
> end fn = count
>
> '~MAIN
> WINDOW #_AccountWnd
>
> FN Initialize
> ON MENU FN doMenus
> ON DIALOG FN doDialog
>
> DO
> HANDLEEVENTS
> FN MyFinderInfo
> UNTIL gTheEnd
>
>
> --
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