Finder Flags

Technote TB 09June 1986

Revised by: Steve Falkenburg November 1993
Jim Friedlander March 1988
Written by: Jim Friedlander June 1986

Changes since March 1988: This version updates the meanings of several of the bits which changed in System 7 and System 7 Pro.

The Finder keeps and uses a series of file information flags for each file. These flags are located in the fdFlags field (a word at offset $28 into an HParamBlockRec) of the ioFlFndrInfo record of a parameter block. For directories, the flags are located in the frFlags field of the ioDrUsrWds record of a parameter block (also offset $28). They may change with newer versions of the Finder. Finder 7.1.1 assigns the following meanings to the flags:

NOTE: The MacBinary II specification instructs downloading applications to clear bits 0, 1, 8, 9, and 10 when downloading a file in MacBinary II format. Downloading applications should actually clear only bits 0 and 8, (the former onDesk bit, and the hasBeenInited bit). Clearing bits 1, 9, or 10 will result in the file being interpreted incorrectly, since bit 1 is now used to store color information, bit 9 tells the system if the file is a letter, and bit 10 informs the Finder if the file has a custom icon.

Further Reference:

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