FSpOpenRF

FSpOpenRF
Header:	Files.h		Carbon status:	Supported

Opens a file’s resource fork.

OSErr FSpOpenRF (
    const FSSpec *spec, 
    SInt8 permission, 
    SInt16 *refNum
);

spec: A pointer to an FSSpec structure specifying the file whose resource fork is to be opened.
permission: A constant indicating the desired file access permissions.
refNum: On return, a pointer to a reference number of an access path to the file’s resource fork. You can pass this reference number as a parameter to any of the low- or high-level file access functions.

function result: A result code.

DISCUSSION

Generally, your application should use Resource Manager functions rather than File Manager functions to access a file’s resource fork. The FSpOpenRF function does not read the resource map into memory and is generally useful only for applications (such as utilities that copy files) that need block-level access to a resource fork. In particular, you should not use the resource fork of a file to hold nonresource data. Many parts of the system software assume that a resource fork always contains resource data.

AVAILABILITY

Supported in Carbon. Available in Mac OS 8.1 and later when Carbon 1.0.2 or later is present.