Technical Q&A QA1449

Setting default open Finder window

Q: How do I set the default Finder window to open when a disk is mounted?

A: The Finder can automatically open specified folders when disks are mounted. This is especially useful when distributing software via CD or disk image.

The third UInt32 of the VolumeHeader's finderInfo field contains the directory ID of a directory whose window should be displayed in the Finder when the volume is mounted, or zero if no directory window should be opened. The Mac OS X Finder does not modify this field.

Listing 1: Setting the volume frOpenChain.

//  Command line tool takes one argument, the path to the directory the Finder will open upon disk mount:
//  SetOpenWindow path/to/directory/to/open

#include <CoreServices/CoreServices.h>

int  main( int argc, const char *argv[] )
{
  OSStatus    err;
  FSRef      dirFSRef;
  FSCatalogInfo  fsCatalogInfo;
  FSVolumeInfo  fsVolumeInfo;

  //  Create an FSRef to the passed in folder we want to automatically open on disk mount
  err  = FSPathMakeRef( (const UInt8 *)argv[1], &dirFSRef, NULL );
  if ( err != noErr )  goto Bail;
  err  = FSGetCatalogInfo( &dirFSRef, kFSCatInfoGettableInfo, &fsCatalogInfo, NULL, NULL, NULL );
  if ( err != noErr )  goto Bail;

  //  In traditional Mac OS, frOpenChain is a list of windows to open. We zero it out for completeness
  ((ExtendedFolderInfo*)&fsCatalogInfo.extFinderInfo)->reserved1  = 0;
  err  = FSSetCatalogInfo( &dirFSRef, kFSCatInfoFinderXInfo, &fsCatalogInfo );
  if ( err != noErr )  goto Bail;

  //  Get the volume finderInfo
  err  = FSGetVolumeInfo( fsCatalogInfo.volume, 0, NULL, kFSVolInfoFinderInfo, &fsVolumeInfo, NULL, NULL );
  if ( err != noErr )  goto Bail;

  //  Set the new folder ID
  ((UInt32*)&(fsVolumeInfo.finderInfo))[2]  = fsCatalogInfo.nodeID;
  err  = FSSetVolumeInfo( fsCatalogInfo.volume, kFSVolInfoFinderInfo, &fsVolumeInfo );
  if ( err != noErr )  goto Bail;

Bail:
  return( err );
}

Document Revision History

Posted: 2006-01-03