Hello, I greatly enjoy and apprieciate using the Cygwin system. I find it to be an extremely useful and important software.
I have a few suggestions on how it could be further improved. On FAT filesystems, additional features of a Unix file system could be provided in the Cygwin file hierarchy by simply creating a file in each directory which would list additional Unix attributes for each file and directory, such as a long case-sensitive file name, drwxrwxrwx, owner and group, along with the actual FAT filename. The attributes and restrictions in the files in the directories, would however of course only be able to restrict access to programs accessing files via the Unix APIs provided by cygwin. However this still is very useful, for instance the sshd server could be used to provide a more secure environment. This is why this sort of feature on top of fat might actually be very useful for running Unix-type programs. The mounts of the entire FAT filesystems (such as those under /mnt) could also be limited via Unix-type permissions too, to only allow certian users access to files in the mount of an entire FAT filesystem. This permission system would by defualt only be used on core direcories/filesystems mounted under /, as a special filesystem type, say which could be called FatUX, "FAT with Unix Extensions". The index file could be called fatux001.idx. The mounts of the entire FAT (X:\) filesystems under /mnt would probably be of a plain FAT type, meaning no additional Unix permissions, and no index files being modified if a Unix program accesses files via that mount. However, of course a user could mount directories as either FAT or FATUX. The mount command could be used with the FAT or FATUX type. I will describe later how the fatux001.idx file can be made unknown to Unix programs without causing any problem. The 001 is just a version number. This file would be created if a Unix program creates the directory via a FATUX mount of the directory, or when a file is added by such a program, or a permission is added to an existing file. If a directory is created by a windows program or a Unix program accessing the directory via a plain FAT mount, a index file is not created until one of the events I just mentioned occurs. As files are added by the user in each directory in the cygwin virtual directory hierarchy system, the index file will be created and added to, the file will contian the case-sensitive Unix filename, the actaul filename under FAT, and the Unix permissions and ownership. Since, many filenames will be able to be created with different case but the same characters, the filename given to Unix programs will have to be different from the actual filename in FAT, for the second and all later filenames with same characters but different case. The first file with say a filename of "Filename.txt", would be simply created as "filename.txt" under FAT. However, a second file name created by a Unix programs with the filename "FIlename.txt" would be created as "filename~1.txt". "FILename.txt" would be filename~2.txt and so on. Each of these files would have an entry in the index file for the directory, such as this: filename~2.txt "FILename.txt" -rw-rw-rw- owner group What if a Unix program tried to create a file named filename~2.txt? Simple, the file would be created as filename~3.txt under FAT, but to unix programs it would be filename~2.txt, since this entry would be added to the index: filename~3.txt "filename~2.txt" -rwxrwxrwx owner group If a filename requested by a Unix program is within two characters of the length limit of the FAT filename, and an ~1 addition must be used as above, two characters will have to be removed from the end of the filename that is written to FAT. If there are three characters needed, for a ~10, for instance, 3 characters will be truncated, 4 for ~100, etc. However, the complete filename requested will of course be written to the directory index file, the filename avialable to Unix programs will not be truncated. However FAT on win95-win98 allows up to over a hundred characters I believe, so this will not be too frequantly needed. The filenames which are truncated when written to FAT, lose some uniqueness due to the loss of the last few characters, however, only if those last few characters made the filename unique will some special attention need to be paid, if the uniqueness is lost, for instance a file a....aa.txt becoming a...~1.txt, and there was a A...aa.txt, it would simply be written to fat as A...~2.txt (the dots are an abbrievation used for this example, representing the 100 or so additional, non-unique (for these two filenames) characters in the filename). Also, the software managing the index files must be able to gracefully account for the fact Windows programs (or a Unix program accessing the directory from a plain FAT mount, not FATUX) may write to the directory and of course not update the index. If a file is created by a Windows programs or via a plain FAt mount, it could be given some defualt permisions, such the permissions of the directory it is in, when it is accessed via a FatUX mount. All of the above would also be used on directories. Here is an example of a possible index file: parent /home/user1 "/home/user1" thisdir /home/user1/myfiles "/home/user1/MyFiles" filename.txt "Filename.txt" -rwxrwxrwx user1 group1 filename~1.txt "FIlename.txt" -rwxrwxrwx user1 group1 myfile.txt "MyFile.txt" -rwxrwxrwx user1 group1 mydirectory "MyDirectory" drw-rw-rw- user1 group1 mydirectory~1 "MYDIrectory" drw-rw-rw- user1 group1 The first two lines are the mappings for the parent and the directory itself. The entry for thisdir should probably also include the "drw-rw-rw- user group" permissions Now, back to the fatux001.idx file. This file need not be visible to Unix programs when a directory is mounted as FatUX, as in accordance with the system I will describe above, if a Unix program wants to create "fatux001.idx", it can, however the file will actaully be given a different name under the actual FAT filesystem, fatux001~1.idx, for instance. An entry then would be added to the index file: fatux001~1.idx "fatux001.idx" -rwxrwxrwx owner group Well, what if a Unix program tried to create a fatux001~1.idx? The file would be created under FAT as fatux001~2.idx, and this would be added to fatue.idx: fatue001~2.idx "fatue001~1.idx" -rwxrwxrwx owner group Of course, if the Unix program is accessing the directory via a plain FAT mount, and not a FATUX mount, the fatue001.idx file would be visible to it, and of course changes made would not update the fatux001.idx. And of course, in that case, all of the actual FAT filenames would be seen by the Unix programs, not the ones in the index file, there would be no permissions, and no case-sensitive etc, since its just a plain FAT mount, not a FATUX mount. A provision may also be made in this index scheme for links. With the file permissions, and ownership features implemented on FAT, these restrictions would apply to processes, each process would inherit the file access permissions of the user it is running as. As well, commands such as su and useradd, chmod, chown, and other such common unix commands would be much more useful and meaningful on Win98 systems, thus creating a much more genuine looking Unix environment. Many users should be able to be easily created and added to passwd. I think implementing this system would be well worth the benefits, and would be useful to a large number of users. __________________________________________________ Do You Yahoo!? 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