1 files changed, 47 insertions, 1 deletions

diff --git a/CPP/7zip/PropID.h b/CPP/7zip/PropID.h
index b818954..2da636f 100644
--- a/CPP/7zip/PropID.h
+++ b/CPP/7zip/PropID.h
@@ -105,7 +105,11 @@ enum
   kpidCopyLink,
   kpidArcFileName,
   kpidIsHash,
-
+  kpidChangeTime,
+  kpidUserId,
+  kpidGroupId,
+  kpidDeviceMajor,
+  kpidDeviceMinor,
 
   kpid_NUM_DEFINED,
 
@@ -127,4 +131,46 @@ const UInt32 kpv_ErrorFlags_DataError             = 1 << 9;
 const UInt32 kpv_ErrorFlags_CrcError              = 1 << 10;
 // const UInt32 kpv_ErrorFlags_Unsupported           = 1 << 11;
 
+/*
+linux ctime :
+   file metadata was last changed.
+   changing the file modification time
+   counts as a metadata change, so will also have the side effect of updating the ctime.
+
+PROPVARIANT for timestamps in 7-Zip:
+{
+  vt = VT_FILETIME
+  wReserved1: set precision level
+    0      : base value (backward compatibility value)
+             only filetime is used (7 digits precision).
+             wReserved2 and wReserved3 can contain random data
+    1      : Unix (1 sec)
+    2      : DOS  (2 sec)
+    3      : High Precision (1 ns)
+    16 - 3 : (reserved) = 1 day
+    16 - 2 : (reserved) = 1 hour
+    16 - 1 : (reserved) = 1 minute
+    16 + 0 : 1 sec (0 digits after point)
+    16 + (1,2,3,4,5,6,7,8,9) : set subsecond precision level :
+         (number of decimal digits after point)
+    16 + 9 : 1 ns  (9 digits after point)
+  wReserved2 = ns % 100 : if     (8 or 9 digits pecision)
+             = 0        : if not (8 or 9 digits pecision)
+  wReserved3 = 0;
+  filetime
+}
+
+NOTE: TAR-PAX archives created by GNU TAR don't keep
+  whole information about original level of precision,
+  and timestamp are stored in reduced form, where tail zero
+  digits after point are removed.
+  So 7-Zip can return different precision levels for different items for such TAR archives.
+*/
+
+/*
+TimePrec returned by IOutArchive::GetFileTimeType()
+is used only for updating, when we compare MTime timestamp
+from archive with timestamp from directory.
+*/
+
 #endif