Execute permissions on downloaded file

问题:

I have made a script for installing a control panel. I've uploaded the script to a server so people can wget it to their machines. The only issue is that you have to chmod it after download. Is there a way to remove this step? How would I go about keeping 755 perms on the downloaded script?

回答1:

When a user downloads the file, the file will automatically get some default permission. In UNIX, each user will have a default set of permissions which apply to all files created by that user, unless you explicitly set it to something else.

This default is called the umask, after the command used to change it. It is either inherited from the login process, or set in the .shrc or .login file which configures an individual account, or it can be run manually.

Typically the default configuration is equivalent to typing 'umask 22' which produces permissions of:

-rw-r--r-- for regular files, or
drwxr-xr-x for directories.

In other words, user has full access, everyone else (group and other) has read access to files, lookup access to directories. As you see above, the execution access is not default for files.

Hence you need to explicitly change it.