Commit | Line | Data |
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1da177e4 LT |
1 | Mount options for ADFS |
2 | ---------------------- | |
3 | ||
4 | uid=nnn All files in the partition will be owned by | |
5 | user id nnn. Default 0 (root). | |
4ae0edc2 | 6 | gid=nnn All files in the partition will be in group |
1da177e4 LT |
7 | nnn. Default 0 (root). |
8 | ownmask=nnn The permission mask for ADFS 'owner' permissions | |
9 | will be nnn. Default 0700. | |
10 | othmask=nnn The permission mask for ADFS 'other' permissions | |
11 | will be nnn. Default 0077. | |
da23ef05 SS |
12 | ftsuffix=n When ftsuffix=0, no file type suffix will be applied. |
13 | When ftsuffix=1, a hexadecimal suffix corresponding to | |
14 | the RISC OS file type will be added. Default 0. | |
1da177e4 LT |
15 | |
16 | Mapping of ADFS permissions to Linux permissions | |
17 | ------------------------------------------------ | |
18 | ||
19 | ADFS permissions consist of the following: | |
20 | ||
21 | Owner read | |
22 | Owner write | |
23 | Other read | |
24 | Other write | |
25 | ||
26 | (In older versions, an 'execute' permission did exist, but this | |
27 | does not hold the same meaning as the Linux 'execute' permission | |
28 | and is now obsolete). | |
29 | ||
30 | The mapping is performed as follows: | |
31 | ||
32 | Owner read -> -r--r--r-- | |
33 | Owner write -> --w--w---w | |
34 | Owner read and filetype UnixExec -> ---x--x--x | |
35 | These are then masked by ownmask, eg 700 -> -rwx------ | |
36 | Possible owner mode permissions -> -rwx------ | |
37 | ||
38 | Other read -> -r--r--r-- | |
39 | Other write -> --w--w--w- | |
40 | Other read and filetype UnixExec -> ---x--x--x | |
41 | These are then masked by othmask, eg 077 -> ----rwxrwx | |
42 | Possible other mode permissions -> ----rwxrwx | |
43 | ||
44 | Hence, with the default masks, if a file is owner read/write, and | |
45 | not a UnixExec filetype, then the permissions will be: | |
46 | ||
47 | -rw------- | |
48 | ||
49 | However, if the masks were ownmask=0770,othmask=0007, then this would | |
50 | be modified to: | |
51 | -rw-rw---- | |
52 | ||
53 | There is no restriction on what you can do with these masks. You may | |
54 | wish that either read bits give read access to the file for all, but | |
55 | keep the default write protection (ownmask=0755,othmask=0577): | |
56 | ||
57 | -rw-r--r-- | |
58 | ||
59 | You can therefore tailor the permission translation to whatever you | |
60 | desire the permissions should be under Linux. | |
da23ef05 SS |
61 | |
62 | RISC OS file type suffix | |
63 | ------------------------ | |
64 | ||
65 | RISC OS file types are stored in bits 19..8 of the file load address. | |
66 | ||
67 | To enable non-RISC OS systems to be used to store files without losing | |
68 | file type information, a file naming convention was devised (initially | |
69 | for use with NFS) such that a hexadecimal suffix of the form ,xyz | |
70 | denoted the file type: e.g. BasicFile,ffb is a BASIC (0xffb) file. This | |
71 | naming convention is now also used by RISC OS emulators such as RPCEmu. | |
72 | ||
73 | Mounting an ADFS disc with option ftsuffix=1 will cause appropriate file | |
74 | type suffixes to be appended to file names read from a directory. If the | |
75 | ftsuffix option is zero or omitted, no file type suffixes will be added. |