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When using GNU stat to probe the filesystem, there are a number of format sequences available for the --format/--printf arguments; this one in particular
%f Raw mode in hex
doesn't make much sense. Comparing with %a, access mode, something might have (you can see this with stat --format '%f %a') a raw mode of 41ed but an access mode of 755, or a raw mode of 81a4 and an access mode of 644.
So what does "raw mode" mean?
There are two parts in deciphering what the "raw mode in hex" means; the first is that it's in hex, but access modes are generally described in octal:
41ed16 = 407758 81a416 = 1006448
If you were to look at /tmp, which typically has the restricted deletion flag ('sticky bit') set:
$ ls -ld /tmp drwxrwxrwt 17 root root 4096 2012-05-31 13:45 /tmp $ stat --format '%f %a' /tmp 43ff 1777
and converting:
43ff16 = 417778
The "raw mode in hex" is described in the programmer's manual for the stat function (man 2 stat), noting that they are octal values:
The following flags are defined for the st_mode field: S_IFMT 0170000 bit mask for the file type bit fields S_IFSOCK 0140000 socket S_IFLNK 0120000 symbolic link S_IFREG 0100000 regular file S_IFBLK 0060000 block device S_IFDIR 0040000 directory S_IFCHR 0020000 character device S_IFIFO 0010000 FIFO S_ISUID 0004000 set UID bit S_ISGID 0002000 set-group-ID bit (see below) S_ISVTX 0001000 sticky bit (see below) S_IRWXU 00700 mask for file owner permissions S_IRUSR 00400 owner has read permission S_IWUSR 00200 owner has write permission S_IXUSR 00100 owner has execute permission S_IRWXG 00070 mask for group permissions S_IRGRP 00040 group has read permission S_IWGRP 00020 group has write permission S_IXGRP 00010 group has execute permission S_IRWXO 00007 mask for permissions for others (not in group) S_IROTH 00004 others have read permission S_IWOTH 00002 others have write permission S_IXOTH 00001 others have execute permission
(Strangely, the online man page is missing this section.)
This is a bit field, and we can see that the last four digits match the access mode; the leading digit (in hex) matches the file type, so a hex mode of 81a4 corresponds to "directory, mode 0644", and a hex mode of 41ed corresponds to "regular file, mode 0775".
from_raw_mode() { _tmp=$(printf '%d' "0x$1"); printf '%s' $((($_tmp >> 9) & 0x7)) $((($_tmp >> 6) & 0x7)) $((($_tmp >> 3) & 0x7)) $(($_tmp & 0x7)); } particularly handy on limited platforms where stat is the only way to get this mode, and it only offers the raw form. Of course if you need to know a particular capability, then it's better just to test that bit directly if you have the raw mode.