Re: FTP Permissions question -- MIDRANGE-L

What does this directory listing from Windows command line FTP mean?
-rwx------ 1 GATES 0 85476 Nov 03 01:35 file.edi

When an FTP client requests a directory listing, it sends the command tothe server, and the server responds with a directory listing. There'sabsolutely nothing in the FTP standard that specifies what this directorylisting should look like. It's human readable, so as long as a human canfigure it out, it's "following the standard".

In this case, it appears that the directory server is trying to make thefile list look like the Unix "ls" command. But, remember, it doesn't HAVEto do this. Any FTP server can send the data in any format it likes, andthat data may or may not include permission information.

If you assume that this really is a Unix directory, and the LS command hasbeen called, then the first bunch of characters lists the permissions for3 different groups:


  -rwx------  = the permissions line

it breaks into:  1 char for object type
                 3 chars for owner's permissions
                 3 chars for group permissions
                 3 chars for everyone else's permissions

In this case, the object type is left off (by specifying a "-") whichmeans that this is a normal file.


The owner's permissions are "rwx".

The group's permissions are "---" which means no permission (files on Unixsystems have two owners, a user profile that's an owner, and a groupprofile that's an owner. You can set the permissions separately foreach.)

Everyone who's not the owner, or a member of the group, falls into thethird category, which is also "---" and it also means "no permission".

The next two fields in the display are "GATES 0". That specifies theowner (GATES) and the group profile (0). In this case, zero means thatthere's no group assigned.


Then comes the file's size, last modification date, and filename.

Does GATES have full rwx authority?

Maybe. If this is a Unix system, he does. If this is a Windows system orsomething else that doesn't actually use Unix-style permissions, then allbets are off.

If it's a non-Unix system, they often emulate the way the Unixdirectory listings look to help certain FTP clients that assume thatthey'll be in this particular format. (Which technically goes against thestandards, but people do it anyway.)

Since those systems don't have the unix permissions system, they may just"fudge" the permissions on the left-hand side in order to make it ascompatible as possible. In this case, I don't know that I'd trust thepermissions.

I'm logged on as BILL. How can I tell my authority from that display?

If you assume that this is a real Unix LS command, then BILL has noauthority to the file because he's not the owner, and only the owner islisted as having any permissions.

Again, if this isn't a real Unix system with real Unix permissions, allbets are off.