Pour gérer les flags (attrib) sur mac os x utiliser la commande : chflags
Attention pour certaines options il faut être root
Par exemple pour autoriser le changement de owner :
chflags nouchg filename
Pour voir les flags d'un fichier : ls -lO
DESCRIPTION
The chflags utility modifies the file flags of the listed files as speci-
fied by the flags operand.
The options are as follows:
-H If the -R option is specified, symbolic links on the command line
are followed. (Symbolic links encountered in the tree traversal
are not followed.)
-L If the -R option is specified, all symbolic links are followed.
-P If the -R option is specified, no symbolic links are followed.
This is the default.
-R Change the file flags for the file hierarchies rooted in the
files instead of just the files themselves.
The flags are specified as an octal number or a comma separated list of
keywords. The following keywords are currently defined:
arch, archived
set the archived flag (super-user only)
opaque set the opaque flag (owner or super-user only). [Directory
is opaque when viewed through a union mount]
nodump set the nodump flag (owner or super-user only)
sappnd, sappend
set the system append-only flag (super-user only)
schg, schange, simmutable
set the system immutable flag (super-user only)
uappnd, uappend
set the user append-only flag (owner or super-user only)
uchg, uchange, uimmutable
set the user immutable flag (owner or super-user only)
hidden set the hidden flag [Hide item from GUI]
As discussed in chflags(2), the sappnd and schg flags may only be unset when the system is in single-user mode.Putting the letters ``no'' before or removing the letters ``no'' from a keyword causes the flag to be cleared. For example:
nouchg clear the user immutable flag (owner or super-user only) dump clear the nodump flag (owner or super-user only)
Unless the -H or -L options are given, chflags on a symbolic link always succeeds and has no effect. The -H, -L and -P options are ignored unless the -R option is specified. In addition, these options override each other and the command's actions are determined by the last one specified.
You can use "ls -lO" to see the flags of existing files.
EXIT STATUS The chflags utility exits 0 on success, and >0 if an error occurs.
SEE ALSO ls(1), chflags(2), stat(2), fts(3), symlink(7)
HISTORY The chflags command first appeared in 4.4BSD.
BUGS Only a limited number of utilities are chflags aware. Some of these tools include ls(1), cp(1), find(1), install(1), dump(8), and restore(8). In particular a tool which is not currently chflags aware is the pax(1) utility.