vRefNum
SFReply structure
#include <StandardFile.h>
typedef struct SFReply { Size Offset Description
Boolean good; 1 0 FALSE if user canceled, etc.
Boolean copy; 1 1 (not used)
OSType fType; 4 2 File type (like OSType), eg: 'TEXT'
short vRefNum; 2 6 Volume number or working
directory ID
short version; 2 8 File version number (normally 0)
unsigned char fName[64]; 64 10 Pascal string filename
} SFReply; 74

Notes: The SFReply structure is used in all Standard File functions, including:
SFPutFile SFPPutFile SFGetFile SFPGetFile
If the good field is FALSE upon return from one of these functions, then the
contents of all other fields are un defined.
The version field will always be 0 on files created by HFS.