TweetFollow Us on Twitter

CopyFile XCMD
Volume Number:5
Issue Number:10
Column Tag:HyperChat™

Related Info: File Manager

XCMD Corner: CopyFile

By Donald Koscheka, Arthur Young & Co., MacTutor Contributing Editor

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

CopyFile XCMD

From time to time I monitor the developer forums on AppleLink and MacNet to see what the rest of the Macintosh development community is up to. Recently, Richard Greenawalt of Foremost Computer Systems issued a request for some help. It seems he needed a routine that copies Macintosh files, data fork, resource fork and finder information.

Not one to miss an opportunity to write an interesting XCMD, I 'linked Rick back and told him that I would be happy to write the routine for him.

The moral of the story is: ask and you might receive. If you need some help with an XCMD or if this column just doesn’t do it for you, let me know; I will be more than happy to help you out. Although I am up on AppleLink, I prefer to use MacNet (KOSCHEKA). If you don’t have access to a modem, write me care of MacTutor.

Copying a Macintosh file is not difficult as long as you keep in mind that Mac files are really two files in one. Each file on the Macintosh has a split personality - the data fork and the resource fork. Although the two forks act as one entity, the file manager treats them as separate files.

CopyFile is a handy little XCMD that lets you copy files from Hypercard. Actually the routine is written to work from any programming milieu which is why I’ve split it into two listings. The first consists of the Hypercard interface. Note that you need to pass both the file name and the working directory id. The second listing contains the actual code, void of any references to Hypercard. This approach lets me build libraries of usable routines that I can use with or without Hypercard, and I intend to use it for all future listings.

The CopyFile function expects to see the name of the input file, the name of the output file and the working directory id’s of both. This gives you some flexibility in naming the copy as well as deciding what folder to put it in. For example, you can concatenate the name of the input file to “copy of “ so that the duplicated file is called “copy of file”. Put this concept in a loop and you get the finder like capability of creating files and naming them “copy of ... “ , “copy of copy of ...” and so on. I chose not to implement this approach because I think the user should have the opportunity to specify the name of the copied file.

Although there are several ways to go about copying a file, I chose a path that goes something like this: First, get the collective size of the data and resource fork along with the finder information about the input file. Using this information, attempt to create a file that is as large as the input file (ie as large as the data and resource fork combined). If the space can be allocated, then copy each fork in turn. If not, delete the newly created file and quit.

Space for each fork is allocated before we do the copy so that we can determine a priori whether the file will fit. To be safe, we reposition the file mark at the beginning of the file before we start copying. If, for any reason, the file copy fails, delete what remains of the file and return the error message to the caller.

The real work is done by the function, CopyFork. This routine will attempt to read the entire fork into a single buffer. Failing that, it divides the size in half until enough memory can be allocated to read some of the fork. Note that copyfork attempts to allocate a buffer large enough to read the entire fork into memory. If that much memory is not available, it keeps dividing the original size by two until a large enough buffer can be allocated.

That’s file copying in a nutshell. It’s not particularly difficult once you realize that you’re really copying two files - the data fork and the resource fork. I’ve tried it with files up to 4 megabytes in size and it works fine.

/**********************************/
/* File: FileCopy.c*/
/* param0 = file reference num*/
/* ( file is open) IN:    */
/* params[0]= name of input */
/* params[1]= wdid of input */
/* params[2]   = name of output  */
/* params[3]   = wdid of output  */
/**********************************/
#include<MacTypes.h>
#include<OSUtil.h>
#include<MemoryMgr.h>
#include<FileMgr.h>
#include<ResourceMgr.h>
#include<pascal.h>
#include<string.h>
#include  “HyperXCMD.h”
#include“HyperUtils.h”

pascal void main( paramPtr )
 XCmdBlockPtr  paramPtr;
/*****************************
*params[0]= name of input 
*params[1]= wdid of input 
*params[2]  = name of output
*params[3]  = wdid of output
*****************************/
{ OSErr err;
 short  inWD;
 short  outWD;
 long   temp;
 Str31  errCode;
 char   inFile[256];
 char   outFile[256];
 paramPtr->returnValue = 0L;
 /*** (1) Get input parameters     ***/
 HLock( paramPtr->params[0] );
 ZeroToPas( paramPtr, *(paramPtr->params[0]), &inFile );
 HUnlock( paramPtr->params[0] );
 inWD = (short)paramtoNum( paramPtr, 1 );
 HLock( paramPtr->params[2] );
 ZeroToPas( paramPtr, *(paramPtr->params[2]), &outFile );
 HUnlock( paramPtr->params[2] );
 outWD = (short)paramtoNum( paramPtr, 3 );
 temp = (long)CopyFile( inFile, inWD, outFile, outWD );
 /*** Flush the output volume ***/
 err = FlushVol( 0L, 0 );
 NumToStr( paramPtr, temp, &errCode );
 paramPtr->returnValue = PasToZero( paramPtr, &errCode );
}

LISTING 1: CopyFile XCMD.


OSErr CopyFork( inref, outref, siz )
 short  inref;   short  outref;  longsiz;
/*****************************
* Given that the caller has opened
* a fork and passed you the names of 
* the input, copy the number of bytes
* from the input fork to the output 
* fork.
* The input mark should be set to 
* start of fork.
* We use a “semi-smart” algorithm
* to do the copy.  If the entire
* fork can be copied, we try doing 
* that, otherwise, we keep dividing
* the size by two until we get enough
* room to read some data in.
******************************/
{
 OSErr  rd_err   = noErr;
 OSErr  wrt_err  = noErr;
 long   rd_len;  /*** actual bytes read ***/
 Ptr    inbuf;
 /*** make sure that the size is even ***/
 if( siz % 2 )
 ++siz;
 if( siz > 0 ){
 do{
 inbuf = NewPtr( siz );
 if( !inbuf )
 siz = ( siz >> 1 );
 }while( !inbuf );
 /*** inbuf is the buffer that we  ***/
 /*** read the data into. If not   ***/
 /*** allocated, don’t attempt to do ***/
 /*** the read   ***/
 if( inbuf ){
 do{
 rd_len = siz;
 rd_err = FSRead( inref, &rd_len, inbuf );
 wrt_err= FSWrite( outref, &rd_len, inbuf );
 }while( !rd_err && !wrt_err );
 
 DisposPtr( inbuf );
 }
 }
 return( wrt_err );
}

OSErr CopyFile( inFile, inWD, outFile, outWD )
 char   *inFile;
 short  inWD; char *outFile;
 short  outWD;
/*****************************
* (1) Determine the size of the input 
* file. 
* (2) Attempt to allocate that 
* much space for the output file.
* (3) If allocation successful,
* create the output file.
* (4) Once the file is created,
* copy the data fork, the resource
* fork and the finder information
* from the input file.
* The file will be called “copy of...”
* Each time we create the file, first
* see if that name exists, if so, keep
* sticking “copy of” onto the name.
******************************/
{
 OSErr  err;
 OSErr  err2;
 short  inref;
 short  outref;
 long   data_eof = 0L;
 long   rsrc_eof = 0L;
 FInfo  fndrinfo;
 /*** (2) Determine how big the input file is ***/
 if( (err = FSOpen( inFile, inWD, &inref )) == noErr){
 err = GetEOF( inref, &data_eof );
 err = FSClose( inref );
 } 
 if( (err = OpenRF( inFile, inWD, &inref )) == noErr ){
 err = GetEOF( inref, &rsrc_eof );
 err = FSClose( inref );  
 }
 /*** (2) Create  output file and allocate space***/
 if( ( err = GetFInfo( inFile, inWD, &fndrinfo ) ) != noErr )
 return( err );
 if( ( err = Create( outFile, inWD, fndrinfo.fdCreator, fndrinfo.fdType 
)) != noErr )
 return( err );
 /*** (3) Try to allocate enough space for both***/
 /*** forks. Note that if we get enough space. ***/
 if( (err = FSOpen( outFile, outWD, &outref )) != noErr)
 return( err );
 if( (err = SetEOF( outref, data_eof  )) != noErr ){
 err2 = FSClose( outref );
 err2 = FSDelete( outFile, outWD );
 return( err );
 }
 err2   = FSClose( outref );
 err  = OpenRF( outFile, outWD, &outref );
 if( (err = SetEOF( outref, rsrc_eof  )) != noErr ){
 err2 = FSClose( outref );
 err2 = FSDelete( outFile, outWD );
 return( err );
 }
 err2 = FSClose( outref );
 /*** (4) Copy the Data fork***/
 err  = FSOpen( inFile, inWD, &inref );
 if( !err ){
 err2   = SetFPos( inref, fsFromStart, 0L );
 err    = CopyFork( inref, outref, data_eof );
 err2   = FSClose( inref );
 err2   = FSClose( outref );
 }
 if( err ){
 err2 = FSDelete( outFile, outWD );
 return( err );
 }
 /*** (5) Now copy the resource fork ***/
 err  = OpenRF( inFile, inWD, &inref );
 if( !err ){
 err2   = SetFPos( inref, fsFromStart, 0L );
 err  = OpenRF( outFile, outWD, &outref );
 err    = CopyFork( inref, outref, rsrc_eof );
 err2   = FSClose( inref );
 err2   = FSClose( outref );
 }
 if( err ){
 err2 = FSDelete( outFile, outWD );
 return( err );
 }
 return( noErr );
}

LISTING 2: CopyFile and CopyFork Functions.

 
AAPL
$100.57
Apple Inc.
+0.04
MSFT
$44.95
Microsoft Corpora
-0.38
GOOG
$584.49
Google Inc.
-2.37

MacTech Search:
Community Search:

Software Updates via MacUpdate

Picasa 3.9.138 - Organize, edit, and sha...
Picasa and Picasa Web Albums allows you to organize, edit, and upload your photos to the Web from your computer in quick, simple steps. Arrange your photos into folders and albums and erase their... Read more
Tidy Up 3.0.15.0 - Find duplicate files...
Tidy Up is a complete duplicate finder and disk-tidiness utility. With Tidy Up you can search for duplicate files and packages by the owner application, content, type, creator, extension, time... Read more
Parallels Desktop 10.0 - Run Windows app...
Parallels Desktop is simply the world's bestselling, top-rated, and most trusted solution for running Windows applications on your Mac. With Parallels Desktop for Mac, you can seamlessly run both... Read more
Apple Final Cut Pro X 10.1.3 - Professio...
Apple Final Cut Pro X is a professional video editing solution.Completely redesigned from the ground up, Final Cut Pro adds extraordinary speed, quality, and flexibility to every part of the post-... Read more
Apple Compressor 4.1.3 - Adds power and...
Compressor adds power and flexibility to Final Cut Pro X export. Customize output settings, work faster with distributed encoding, and tap into a comprehensive set of delivery features. Powerful... Read more
Chromium 36.0.1985.143 - Fast and stable...
Chromium is an open-source browser project that aims to build a safer, faster, and more stable way for all Internet users to experience the web. FreeSMUG-Free OpenSource Mac User Group build is... Read more
Macgo Blu-ray Player 2.10.6.1691 - Blu-r...
Macgo Mac Blu-ray Player can bring you the most unforgettable Blu-ray experience on your Mac. Overview Macgo Mac Blu-ray Player can satisfy just about every need you could possibly have in a Blu-ray... Read more
Apple Motion 5.1.2 - Create and customiz...
Apple Motion is designed for video editors, Motion 5 lets you customize Final Cut Pro titles, transitions, and effects. Or create your own dazzling animations in 2D or 3D space, with real-time... Read more
A Better Finder Rename 9.39 - File, phot...
A Better Finder Rename is the most complete renaming solution available on the market today. That's why, since 1996, tens of thousands of hobbyists, professionals and businesses depend on A Better... Read more
PopChar X 6.6 - Floating window shows av...
PopChar X helps you get the most out of your font collection. With its crystal-clear interface, PopChar X provides a frustration-free way to access any font's special characters. Expanded... Read more

Latest Forum Discussions

See All

Fallin Love - The Game of Love (Games)
Fallin Love - The Game of Love 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: GRAVITATE AROUND LOVE | Read more »
Cubic Castles Review
Cubic Castles Review By Rob Thomas on August 20th, 2014 Our Rating: :: CASTLE CRAFTINGiPad Only App - Designed for the iPad Some ridiculously frustrating camera issues aside, Cubic Castles is a pretty neat, voxel-based crafting... | Read more »
Space Colors – Tips, Tricks, Strategies,...
Hello Cadets: Want to know what we thought about this hectic space combat/roguelike? Check out our Space Colors review! Space Colors is a cool shooter/roguelike from Team Chaos. You travel from planet to planet across a huge galaxy and complete a... | Read more »
Tap Sports Baseball – Tips, Tricks, and...
Tap Sports Baseball is a pretty simple game to learn, but that doesn’t mean it’s an easy game to master, by any means. To start your batting career off well, we thought we’d give you the heads up on some handy tips and tricks. Hey Batter-Batter:... | Read more »
Tap Sports Baseball Review
Tap Sports Baseball Review By Jennifer Allen on August 20th, 2014 Our Rating: :: LET'S PLAY BALLUniversal App - Designed for iPhone and iPad Tap Sports Baseball is briefly fun but lacks some important features.   | Read more »
Earn to Die 2 Set to Drive in to the App...
Earn to Die 2 Set to Drive in to the App Store Later This Year Posted by Ellis Spice on August 20th, 2014 [ permalink ] Not Doppler has announced that Earn to Die 2, a sequel to their successful game | Read more »
Frontier Heroes Review
Frontier Heroes Review By Andrew Fisher on August 20th, 2014 Our Rating: :: BLAZES NO TRAILSUniversal App - Designed for iPhone and iPad Despite awesome visuals and great music, Frontier Heroes just doesn’t quite deliver enough fun... | Read more »
Echo Prime is Now on Sale for $0.99
Echo Prime is Now on Sale for $0.99 Posted by Jessica Fisher on August 20th, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Star Realms Review
Star Realms Review By Andrew Fisher on August 20th, 2014 Our Rating: :: A STAR IS BORNUniversal App - Designed for iPhone and iPad Star Realms is an excellent adaptation of an outstanding deck-builder. With great visuals and an... | Read more »
This. Is. SPRINGFIELD! War comes to The...
This. Is. SPRINGFIELD! | Read more »

Price Scanner via MacPrices.net

Apple now offering certified refurbished 2014...
 The Apple Store is now offering Apple Certified Refurbished 2014 MacBook Airs for up to $180 off the cost of new models. An Apple one-year warranty is included with each MacBook, and shipping is... Read more
Best Buy’s College Student Deals: $100 off Ma...
Take an additional $100 off all MacBooks and iMacs, $50 off iPad Airs and iPad minis, at Best Buy Online with their College Students Deals Savings, valid through September 6th. Anyone with a valid .... Read more
MacBook Airs on sale for $100 off MSRP, free...
B&H Photo has three 2014 MacBook Airs on sale for $100 off MSRP. Shipping is free, and B&H charges NY sales tax only. They also include free copies of Parallels Desktop and LoJack for Laptops... Read more
Razer Taipan Mouse For Gamers And Non-Gamers...
If you’re a serious gamer on either Mac or Windows PCs, a serious gaming mouse is a necessity for first-tier performance. However, even if like me you’re not much of a gamer, there’s still a strong... Read more
15-inch 2.2GHz MacBook Pro on sale for $1899,...
Adorama has the new 15″ 2.2GHz Retina MacBook Pro on sale for $1899 including free shipping plus NY & NJ sales tax only. Their price is $100 off MSRP, and it’s the lowest price available for this... Read more
Mid-Size Tablet Shootout Posted: iPad mini wi...
I ‘m curious about how many iPads Apple is actually selling these days. It’s been widely rumored and anticipated that new models with A8 SoCs, 2 GB of RAM, 8 megapixel cameras, and fingerprint... Read more
The 15 Biggest iPad Air Problems And How To A...
What’s this? Fifteen “biggest” problems with the iPad Air? Does that mean there are a lot of smaller problems as well? Say it isn’t so! My old iPad 2 has manifested no hardware problems in three... Read more
TYLT Syncable-Duo, 2-in-1 USB Cable With Appl...
TYLT has introduced the Syncable-Duo, a universal cable solution for charging and syncing data to smartphones and tablets. The Syncable-Duo eliminates the need for multiple cables by incorporating... Read more
Save up to $140 off MSRP with Apple refurbish...
Apple is offering Certified Refurbished iPad Airs for up to $140 off MSRP. Apple’s one-year warranty is included with each model, and shipping is free. Stock tends to come and go with some of these... Read more
2.5GHz Mac mini on sale for $549, save $50
B&H Photo has the 2.5GHz Mac mini on sale for $549.99 including free shipping. That’s $50 off MSRP, and B&H will also include a free copy of Parallels Desktop software. NY sales tax only. Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Senior Event Manager, *Apple* Retail Market...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global event strategy. Delivering an overarching brand story; in-store, Read more
*Apple* Solutions Consultant - Apple (United...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Position Opening at *Apple* - Apple (United...
**Job Summary** Being a Business Manager at an Apple Store means you're the catalyst for businesses to discover and leverage the power, ease, and flexibility of Apple Read more
Position Opening at *Apple* - Apple (United...
**Job Summary** At the Apple Store, you connect business professionals and entrepreneurs with the tools they need in order to put Apple solutions to work in their Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.