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Important: The information in this document is obsolete and should not be used for new development.

Chapter 3 - Standard File Package / Standard File Package Reference

Application-Defined Routines / File Filter Functions

MyCustomFileFilter
A file filter function whose address is passed to CustomGetFile should have the following form:
FUNCTION MyCustomFileFilter (pb: CInfoPBPtr; myDataPtr: Ptr):
                               Boolean;
pb
A pointer to a catalog information parameter block.
myDataPtr
A pointer to the optional data whose address is passed to CustomGetFile.

DESCRIPTION
When CustomGetFile is displaying the contents of a volume or folder, it checks the file type of each file and filters out files whose types do not match your application's specifications. If your application also supplies a file filter function, the Standard File Package calls that function each time it identifies a file of an acceptable type.
When your file filter function is called, it is passed, in the pb parameter, a pointer to a catalog information parameter block. See the chapter "File Manager" in this book for
a description of the fields of this parameter block.
Your function evaluates the catalog information parameter block and returns a Boolean value that determines whether the file is filtered (that is, a value of TRUE suppresses display of the filename, and a value of FALSE allows the display). If you do not supply a file filter function, the Standard File Package displays all files of the specified types.

SEE ALSO
See "Writing a File Filter Function" on page 3-20 for a sample file filter function.