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System: ( lsb_release -a )

Distributor ID: Ubuntu
Description:    Ubuntu 10.04.4 LTS
Release:        10.04
Codename:       lucid

This is my command:

sudo chmod +a "www-data allow delete,write,append,file_inherit,directory_inherit" app/cache app/logs



chmod: invalid mode: `+a'
Try `chmod --help' for more information.

Why doesn't this work? Isn't the +a standard chmod?


Looks like this is a OSX only mod:

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try +x instead of +a – Ashu Jun 5 '12 at 13:48
up vote 14 down vote accepted

"+a" is not a standard argument, no. Follow the next step in the linked documentation.

sudo setfacl -R -m u:www-data:rwx -m u:`whoami`:rwx app/cache app/logs
sudo setfacl -dR -m u:www-data:rwx -m u:`whoami`:rwx app/cache app/logs

Info on what the "+a" does for chmods that use it:

+a The +a mode parses a new ACL entry from the next argument on the commandline and inserts it into the canonical location in the ACL. If the supplied entry refers to an identity already listed, the two entries are combined.

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Thanks, needed to install the setfacl package – Phill Pafford Jun 5 '12 at 13:57

That is Mac OS X syntax. See here for proof.
Ubuntu's chmod doesn't include this option.

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