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  “HyperXCMD.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 );


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 )
 if( siz > 0 ){
 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 ){
 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.


Community Search:
MacTech Search:

Software Updates via MacUpdate

Google Earth Web Plug-in - Em...
Google Earth Plug-in and its JavaScript API let you embed Google Earth, a true 3D digital globe, into your Web pages. Using the API you can draw markers and lines, drape images over the terrain, add... Read more
Spotify - Stream music, creat...
Spotify is a streaming music service that gives you on-demand access to millions of songs. Whether you like driving rock, silky R&B, or grandiose classical music, Spotify's massive catalogue puts... Read more
Google Chrome 54.0.2840.71 - Modern and...
Google Chrome is a Web browser by Google, created to be a modern platform for Web pages and applications. It utilizes very fast loading of Web pages and has a V8 engine, which is a custom built... Read more
HoudahSpot 4.2.6 - Advanced file-search...
HoudahSpot is a powerful file search tool. Use HoudahSpot to locate hard-to-find files and keep frequently used files within reach. HoudahSpot will immediately feel familiar. It works just the way... Read more
Yummy FTP Pro 1.11.11 - $29.99
Yummy FTP Pro is an advanced Mac file transfer app which provides a full-featured professional toolkit combined with blazing speeds and impeccable reliability, so whether you want to transfer a few... Read more
Shimo - VPN client – for everyon...
Shimo is the most versatile VPN client for OS X and it enables really everybody to master secure network. It supports more protocols than any other VPN application out there! CiscoVPN, AnyConnect,... Read more
Dash 3.4.0 - Instant search and offline...
Dash is an API documentation browser and code snippet manager. Dash helps you store snippets of code, as well as instantly search and browse documentation for almost any API you might use (for a full... Read more
AirRadar 3.1.9 - $9.95
With AirRadar, scanning for wireless networks is now easier and more personalized! It allows you to scan for open networks and tag them as favourites or filter them out. View detailed network... Read more
Printopia 2.1.22 - Share Mac printers wi...
Run Printopia on your Mac to share its printers to any capable iPhone, iPad or iPod Touch. Printopia will also add virtual printers, allowing you to save print-outs to your Mac and send to apps.... Read more
SteerMouse 5.0 - Powerful third-party mo...
SteerMouse is an advanced driver for USB and Bluetooth mice. It also supports Apple Mighty Mouse very well. SteerMouse can assign various functions to buttons that Apple's software does not allow,... Read more

Latest Forum Discussions

See All

5 Halloween mobile games for wimps
If you're anything like me, horror games are a great way to have nightly nightmares for the next decade or three. They're off limits, but perhaps you want to get in on the Halloween celebrations in some way. Fortunately not all Halloween themed... | Read more »
The 5 scariest mobile games
It's the most wonderful time of the year for people who enjoy scaring themselves silly with haunted houses, movies, video games, and what have you. Mobile might not be the first platform you'd turn to for quality scares, but rest assured there are... | Read more »
Lifeline: Flatline (Games)
Lifeline: Flatline 1.0.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0.0 (iTunes) Description: The Lifeline series takes a terrifying turn in this interactive horror experience. Every decision you make could help... | Read more »
Game of Dice is now available on Faceboo...
After celebrating its anniversary in style with a brand new update, there’s even more excitement in store for Game of Dice has after just being launched on Facebook Gameroom. A relatively new platform, Facebook Gameroom has been designed for PC... | Read more »
4 addictive clicker games like Best Fien...
Clickers are passive games that take advantage of basic human psychology to suck you in, and they're totally unashamed of that. As long as you're aware that this game has been created to take hold of your brain and leave you perfectly content to... | Read more »
Smile Inc. Guide: How not to die on the...
As if Mondays weren't bad enough, at Smile Inc. you have to deal with giant killer donuts, massive hungry staplers, and blasting zones. It's not exactly a happy, thriving work environment. In fact, you'll be lucky to survive the nine to five.... | Read more »
Oh...Sir! The Insult Simulator (Games)
Oh...Sir! The Insult Simulator 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: | Read more »
WitchSpring2 (Games)
WitchSpring2 1.27 Device: iOS Universal Category: Games Price: $3.99, Version: 1.27 (iTunes) Description: This is the story of Luna, the Moonlight Witch as she sets out into the world. This is a sequel to Witch Spring. Witch Spring 2... | Read more »
4 popular apps getting a Halloween makeo...
'Tis the season for all things spooky. So much, so, in fact, that even apps are getting into the spirt of things, dressing up in costume and spreading jack o' lanterns all about the place. These updates bring frightening new character skins, scary... | Read more »
Pokémon GO celebrates Halloween with can...
The folks behind Pokémon GO have some exciting things planned for their Halloween celebration, the first in-game event since it launched back in July. Starting October 26 and ending on November 1, trainers will be running into large numbers of... | Read more »

Price Scanner via

Macs’ Superior Enterprise Deployment Cost Eco...
IBM’s debunking of conventional wisdom and popular mythology about the relative cost of using Apple Mac computers as opposed to PCs running Microsoft Windows at the sixth annual Jamf Nation User... Read more
12-inch WiFi Apple iPad Pros on sale for $50-...
B&H Photo has 12″ WiFi Apple iPad Pros on sale for $50-$70 off MSRP, each including free shipping. B&H charges sales tax in NY only: - 12″ Space Gray 32GB WiFi iPad Pro: $749 $50 off MSRP -... Read more
Apple refurbished 12-inch 128GB iPad Pros ava...
Apple has Certified Refurbished 12″ Apple iPad Pros available for up to $160 off the cost of new iPads. An Apple one-year warranty is included with each model, and shipping is free: - 32GB 12″ iPad... Read more
Apple refurbished iPad minis and iPad Air 2s...
Apple recently dropped prices on several Certified Refurbished iPad mini 4s and 2s as well as iPad Air 2s. An Apple one-year warranty is included with each model, and shipping is free: - 16GB iPad... Read more
MacHTTP-js Preview Full-featured Web Server f...
MacHTTP.Org has released MacHTTP-js Preview for macOS, a full-featured Web server for 21st Century desktops and servers. MacHTTP-js is a modern take on the classic stand-alone, desktop computer Web... Read more
Samsung Galaxy Tab A 10.1 with S Pen Makes US...
Samsung Electronics America, Inc. has announced the release of the Galaxy Tab A 10.1 with S Pen in a highly mobile, lightweight tablet. “With an embedded S Pen, consumers can discover more ways to... Read more
13-inch 2.5GHz MacBook Pro (Apple refurbished...
Apple has Certified Refurbished 13″ 2.5GHz MacBook Pros available for $829, or $270 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free: - 13″ 2.5GHz MacBook Pros... Read more
27-inch iMacs on sale for up to $220 off MSRP
B&H Photo has 27″ Apple iMacs on sale for up to $200 off MSRP including free shipping plus NY sales tax only: - 27″ 3.3GHz iMac 5K: $2099 $200 off MSRP - 27″ 3.2GHz/1TB Fusion iMac 5K: $1899.99 $... Read more
13-inch 2.5GHz MacBook Pro available for $927...
Overstock has the 13″ 2.5GHz MacBook Pro available for $926.99 including free shipping. Their price is $172 off MSRP. Read more
Apple refurbished 2015 13-inch MacBook Airs a...
Apple has Certified Refurbished 2015 13″ MacBook Airs available starting at $759. An Apple one-year warranty is included with each MacBook, and shipping is free: - 2015 13″ 1.6GHz/4GB/128GB MacBook... Read more

Jobs Board

*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
Software Engineering Intern: UI Applications...
Job Summary Apple is currently seeking enthusiastic interns who can work full-time for a minimum of 12-weeks between Fall 2015 and Summer 2016. Our software Read more
Security Data Analyst - *Apple* Information...
…data sources need to be collected to allow Information Security to better protect Apple employees and customers from a wide range of threats.Act as the subject Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Solutions Consultant - Apple (United...
# Apple Solutions Consultant Job Number: 52812872 Houston, Texas, United States Posted: Oct. 18, 2016 Weekly Hours: 40.00 **Job Summary** As an Apple Solutions Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.