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Re: xampp install-wrong user name-tinycore linux

PostPosted: 12. January 2009 21:34
by glitzi85
Usernames are just a nice visual style for the guy sitting in front of the monitor. If you want to access some folder, Linux is comparing your UID with the UID of the folder, and if you have sufficient rights, you will be able to access this folder. In tarballs, the uid, gid and permission of the file are saved. When you make an untar, then the uid and gid are restored. If these uid/gid does not exist on your computer then just the number is displayed. Because of this, all important usernames should have the same uid on every Linux system. root = 0 and nobody = highest available uid.

If you would now tar an folder inside your home directory, then your uid will be saved. Let's make an example:

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drwxr-xr-x   tc  root  1024  testfolder


On your system, user tc has the uid 1001. Now you tar the folder, and extract it on another computer. Let's assume you have an user called dummy with the uid 1001 on that other computer. After untaring the folder, it will look like this:

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drwxr-xr-x   dummy  root  1024  testfolder


On a system without an user having the uid 1001 it would look like this:

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drwxr-xr-x   1001  root  1024  testfolder


You understand what i mean?

glitzi

Re: xampp install-wrong user name-tinycore linux

PostPosted: 12. January 2009 23:55
by bigpcman
Yes I understand completely. According to the tiny core forum moderators the uid for the user nobody is not the same from one linux distro to the next and not specified as a standard of any kind so it would seem that the xampp folks should point this out in their faq since the consequences are very hard to track down. Anyway thanks for your help it explained an important aspect of the tar system I was not aware of.

Re: xampp install-wrong user name-tinycore linux

PostPosted: 13. January 2009 00:25
by glitzi85
Yes, only the root uid is defined as 0. Most distros using also the "nobody = highest available uid" system. But your right, it should be noted somewhere. I just have no idea where it should be noted, as i normally do not use the AF Documentation.

glitzi