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.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Luminar 1.2.1 - Powerful, adaptive, conf...
Luminar is the new full-featured image editor that adapts to the way you edit photos. Over 300 essential tools to fix, edit, and enhance your photos with comfort. The future of photo editing is here... Read more
1Password 6.8.1 - Powerful password mana...
1Password is a password manager that uniquely brings you both security and convenience. It is the only program that provides anti-phishing protection and goes beyond password management by adding Web... Read more
EtreCheck 3.4.4 - For troubleshooting yo...
EtreCheck is an app that displays the important details of your system configuration and allow you to copy that information to the Clipboard. It is meant to be used with Apple Support Communities to... Read more
GarageSale 7.0.8 - Create outstanding eB...
GarageSale is a slick, full-featured client application for the eBay online auction system. Create and manage your auctions with ease. With GarageSale, you can create, edit, track, and manage... Read more
Backblaze 5.0.0.116 - Online backup serv...
Backblaze is an online backup service designed from the ground-up for the Mac. With unlimited storage available for $5 per month, as well as a free 15-day trial, peace of mind is within reach with... Read more
Parallels Desktop 13.0.0 - Run Windows a...
Parallels allows you to run Windows and Mac applications side by side. Choose your view to make Windows invisible while still using its applications, or keep the familiar Windows background and... Read more
Mellel 4.0.0 - The word processor for sc...
Mellel is the leading word processor for OS X and has been widely considered the industry standard for long form documents since its inception. Mellel focuses on writers and scholars for technical... Read more
Adobe Muse CC 2017 2017.1.0 - Design and...
Muse CC 2017 is available as part of Adobe Creative Cloud for as little as $14.99/month (or $9.99/month if you're a previous Muse customer). Adobe Muse 2017 enables designers to create websites as... Read more
WhatsApp 0.2.5862 - Desktop client for W...
WhatsApp is the desktop client for WhatsApp Messenger, a cross-platform mobile messaging app which allows you to exchange messages without having to pay for SMS. WhatsApp Messenger is available for... Read more
WhatsApp 0.2.5862 - Desktop client for W...
WhatsApp is the desktop client for WhatsApp Messenger, a cross-platform mobile messaging app which allows you to exchange messages without having to pay for SMS. WhatsApp Messenger is available for... Read more

Radiation City (Games)
Radiation City 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Radiation City Welcome to the world of Radiation City where a great survival adventure awaits you! | Read more »
The best deals on the App Store this wee...
The summer is drawing quickly to a close, but luckily there's a game for every season. It's an excellent week for some bargain shopping if that's what you're after. There are some big names and indie darlings in this week's roundup. It's a great... | Read more »
KORG iMono/Poly (Music)
KORG iMono/Poly 1.0.0 Device: iOS Universal Category: Music Price: $19.99, Version: 1.0.0 (iTunes) Description: *** Special Sale for a limited time to celebrate the debut of KORG iMono/Poly (33% OFF) until Sep 30! *** Reviving a... | Read more »
Super Phantom Cat 2 beginner's guid...
Super Phantom Cat 2 presents a whole new world of fun platforming challenges and perplexing puzzles. It's a well-designed platformer with a bright, neon aesthetic that brings the genre up to date. [Read more] | Read more »
Shadow Fight 2 Special Edition (Games)
Shadow Fight 2 Special Edition 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: ** New story chapter! **** No Ads! **** No energy! ** The best fighting series on mobile has returned and... | Read more »
4 RPGs like Final Fantasy XV that deserv...
Square Enix announced another Final Fantasy XV spin-off today - Final Fantasy XV Pocket Edition. This mobile, episodic version of the hit RPG gives the game a chibi-fied makeover. The first episode will be free, followed by 9 more premium episodes... | Read more »
Guild sieges and soul gems in latest upd...
Webzen’s MU Origin hit app stores last year, giving fans of fantasy hack-n-slash MMOs like Diablo a new fix to fixate on. This latest update introduces a competitive guild battle, a fresh dungeon challenge, a mini-game and some elemental gems to... | Read more »
Little Red Lie (Games)
Little Red Lie 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: ARE YOU MORE AFRAID OF POVERTY THAN DEATH? Little Red Lie is a narrative-focused, interactive fiction experience that reduces... | Read more »
You can now apply to be Clash of Clans...
Earlier this month, word got out that the Builder, the trusty handiman who tirelessly built every single building inevery singleClash of Clansbase had called it quits. Sick of seeing his work destroyed endless, the Builder has set out for our world... | Read more »
Meshi Quest beginner's guide - how...
Meshi Quest is Square Enix's newest free-to-play release, and it's a real charmer. You start off as the head of a sushi restaurant, upgrading your food and equipment as you serve visitors heaping helpings of your delicious meals. As you progress,... | Read more »

Price Scanner via MacPrices.net

Low Cost Subscription Graphics App Alternativ...
I’m not a fan of the subscription software model, I don’t use any subscription apps. Used to be that you paid your license fee and the app was yours to use indefinitely, or until one opted for a paid... Read more
Clearance 2016 13-inch MacBook Airs, Apple re...
Apple has Certified Refurbished 2016 13″ MacBook Airs available starting at $809. An Apple one-year warranty is included with each MacBook, and shipping is free: – 13″ 1.6GHz/8GB/128GB MacBook Air: $... Read more
2017 13-inch MacBook Airs on sale for $100 of...
B&H Photo new 2017 13″ MacBook Airs on sale today for $100 off MSRP, starting at $899: – 13″ 1.8GHz/128GB MacBook Air (MQD32LL/A): $899, $100 off MSRP – 13″ 1.8GHz/256GB MacBook Air (MQD42LL/A... Read more
Sale! 13-inch 2.3GHz MacBook Pros for $100 of...
B&H Photo has 13″ 2.3GHz MacBook Pros in stock today and on sale for $100 off MSRP including free shipping plus NY & NJ sales tax only: – 13-inch 2.3GHz/128GB Space Gray MacBook Pro (MPXQ2LL... Read more
2016 MacBook Pros, Apple refurbished, availab...
Apple has Certified Refurbished 2016 15″ and 13″ MacBook Pros available starting at $1189. An Apple one-year warranty is included with each model, and shipping is free: – 15″ 2.7GHz Touch Bar Space... Read more
Apple offers Certified Refurbished iPhone 6s...
Apple has Certified Refurbished unlocked iPhone 6s’s and 6s Plus’s available starting at $449. An Apple one-year warranty is included with each phone, and shipping is free: – 16GB iPhone 6s: $449, $... Read more
Apple offers Certified Refurbished Pencils fo...
Apple has Certified Refurbished Apple Pencils available for $85 including free shipping. Their price is $14 off MSRP, and it’s the lowest price available for a Pencil. Read more
2016 15-inch 2.6GHz Touch Bar MacBook Pro ava...
B&H Photo has clearance 2016 15″ 2.6GHz MacBook Pros in stock today and on sale for $500 off original MSRP. Shipping is free, and B&H charges NY & NJ sales tax only: – 15″ 2.6GHz Touch... Read more
21-inch 2.3GHz iMac on sale for $999, save $1...
Amazon has the new 2017 21″ 2.3GHz iMac (MMQA2LL/A) in stock and on sale for $999.99 including free shipping. Their price is $100 off MSRP, and it’s the lowest price available for this model. Read more
Free Instant Translator 2.0 App For iOS Relea...
Mobile application development company, Neoappz has announced the release and immediate availability of Instant Translator 2.0 for iOS devices. Instant Translator is a user-friendly application which... Read more

Jobs Board

*Apple* Solutions Consultant - Apple Inc. (U...
Job Summary As an Apple Solutions Consultant, you'll be the link between our future customers and our products. You'll showcase your entrepreneurial spirit as you Read more
*Apple* Solutions Consultant - Apple Inc. (U...
…about helping others on a team while also delighting customers? As an Apple Solutions Consultant (ASC), you will discover customers needs and help connect them Read more
Sr. Software Engineer, Core Services, *Apple...
…part of the server team that powers various features within the App Store, Apple Music, iBooks, iTunes, and Podcasts. You will be working cross functionally with Read more
SW Engineer *Apple* TV Frameworks - Apple I...
Job Summary The Apple TV team is looking for a software engineer to join us as we work to define the future of the tvOS platform. Key Qualifications You're 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
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.