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Your Personal Files and Directories

Open-door policies are very supportive environments for collaborative efforts. In such an environment, the sharing of information and ideas happen easily. For this reason, MSRI supports a directory structure that permits members to share files and other content, without having to know a lot of Unix-specific commands to make this happen.

Under our current structure, member home directories are created with permission 711 (rwx--x--x). Files are created with default permissions of 600 (rw-------). This gives the owner of the file/directory, complete control to edit, remove or in the case of a program, execute. Under this scheme, other users can get to any publicly-accessible directories or files [with group- or world-readable permissions] in your home directory, but they cannot get a list of the files in your home directory or read your files by default. They do not have any permissions to modify or remove files or folders.

As the owner of an account, you have all the rights you need to set or reset permissions on your files. If you prefer less stringent permissions on your personal files, you are free to change them using the information provided here.

The following actions can be taken to permit access to personal files and directories:

  • All user accounts contain a directory named Public. Content that should be accessible by anyone other than the owner of the account should be placed in this directory. It has permissions 755 (rwxr-xr-x). This grants full access to the owner, and read access to everyone else. In order to share a file, make sure it is readable to others and move it to your Public folder. We have provided a command, share which changes permissions to be world-readable. A simple way to ensure all files in your Public folder are world-readable is to run the command:
    share ~/Public/*


  • We advise using the umask command to set the value of default permissions for new files and directories. Briefly, the umask specifies the bits in the permission string that should be turned off. Currently the default umask is 066--meaning that all read & write permissions for anyone but the owner are removed. A umask defined in the user space, such as in a personal .cshrc.extra file, overrides any system-wide setting previously established.


  • You may use the "share" command to change permissions of any files you own--The "Public" folder is provided to you as a convenience, but you need not confine your world-readable files to it.

We hope this information is helpful. Please send any questions to computing@msri.org.