Today a colleague copied a Together project from his Windows machine to my USB stick, from which I copied the files to my disk. The files were write protected on the Windows machine since the project was managed by Synergy. When I tried to remove write protection from these files I realized that the files were not read-only by standard Unix file attributes and I could not use chmod to write-enable the files. When opening the properties dialog on those files one could see that the flag “Geschützt” (Protected) is set. Since the project consists of some hundred files using the dialog to remove this flag is no option.
After some searching I found this article which explains that OS X has some additional flags that supersede the standard UNIX permissions. These additional flags can be listed with ls by adding the -O option:
ls -AlO total 152 -rw-r--r--@ 1 thoms thoms hidden 6148 17 Mai 17:56 .DS_Store -rwxrwxrwx 1 thoms thoms - 312 7 Mai 2009 .checkstyle -rwxrwxrwx 1 thoms thoms - 234 5 Jun 2009 .designRoot -rwxrwxrwx 1 thoms thoms - 48559 6 Mai 2009 .pmd -rwxrwxrwx 1 thoms thoms - 922 21 Okt 2009 .project drwxrwxrwx 6 thoms thoms uchg 204 17 Mai 17:52 Dokumente drwxrwxrwx 11 thoms thoms uchg 374 17 Mai 17:52 Model Folder -rwxrwxrwx 1 thoms thoms uchg 71 7 Mai 10:36 _ccmwaid.inf -rwxrwxrwx 1 thoms thoms uchg 1583 23 Jul 2008 grafiken.tpl
The flags can be read and manipulated with the chflags command. For unsetting the “user immutability flag” on a complete directory execute
chflags -R nouchg *
