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Chapter 2 - File Manager / Using the File Manager

Creating File System Specification Records

Sometimes it is useful for your application to create a file system specification record. For example, your application might be running in an environment where the enhanced Standard File Package routines (which return FSSpec records) are unavailable but the File Manager routines that accept FSSpec records are available (perhaps as glue code in your development system). You can call the FSMakeFSSpec function (or its low-level equivalent PBMakeFSSpec) to initialize a file system specification record.

Three of the parameters to FSMakeFSSpec represent the volume, parent directory, and file specifications of the target object. You can provide this information in any of the four combinations described in "HFS Specifications" beginning on page 2-28. Table 2-10 details the ways your application can identify the name and location of a file or directory in a call to FSMakeFSSpec.

The fourth parameter to FSMakeFSSpec is a pointer to the FSSpec record.

Table 2-10 How FSMakeFSSpec interprets its parameters

vRefNum	dirID	fileName	Interpretation
Ignored	Ignored	Full pathname	Full pathname overrides any other information
Volume reference number or drive number	Directory ID	Partial pathname	Partial pathname starts in the directory whose parent is specified in the dirID parameter
Working directory reference number	Directory ID	Partial pathname	Directory specification in the dirID parameter overrides the directory implied by the reference number Partial pathname starts in the directory whose parent is specified in dirID
Volume reference number or drive number	0	Partial pathname	Partial pathname starts in the root directory of the volume in vRefNum
Working directory reference number	0	Partial pathname	Partial pathname starts in the directory specified by the working directory reference number
Volume reference number of drive	Directory ID	Empty string or NIL	The target object is the directory specified by the directory ID in dirID
Working directory reference number	0	Empty string or NIL	The target object is the directory specified by the working directory reference number in vRefNum
Volume reference number or drive number	0	Empty string or NIL	The target object is the volume specified in vRefNum
0	Directory ID	Empty string or NIL	The target object is the directory specified in dirID on the default volume
0	Directory ID	Partial pathname	Partial pathname starts in the directory specified in dirID on the default volume
0	0	Empty string or NIL	The target object is the default directory on the default volume
0	0	Partial pathname	Partial pathname starts in the default directory on the default volume