SECW Chunk

See more on Chunks in general.

This is Security information, Windows-style

SECW Chunk structure


The a (correlated) Flag must be set.

The b (subtype) Flag must be set.

The r (range of instances) , p (multi-part) & c, and y (payload specification) flags are all available. The i (instance sizes field is present) flag must be set if and only if the r flag is set.

The y flag may be present. The COMP#69 is specifically designed for this chunk.

FATR-nd has a distinct meaning, documented below.


Subtype is set to 67 (hex 43).

Instance Number

The Instance Number matches the Instance Number of the DATA it applies to, as with any a-flagged chunk type.

SECW Chunk Payload

The Payload contains lpbinary values for the Owner SID, Group SID, and DACL of the file or directory. Use these values with the SetSecurityInfo function in the Win32 API.

Usage Notes

This probably is not usable on platforms other than Windows.


SECW-nd Chunk

A portion number, as with DATA.

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