When could or should I use chmod g+s on a file or directory?

Question

In deploying to a new (Solaris 9) environment recently, one of the steps was to copy a set of files and directories to their new location and then to apply the group UID bit (us

Answer 1

Here is very handy explanation of SGID (chmod g+s): http://www.linuxnix.com/sgid-set-sgid-linuxunix/

SGID (Set Group ID up on execution) is a special type of file permissions given to a file/folder. Normally in Linux/Unix when a program runs, it inherits access permissions from the logged in user. SGID is defined as giving temporary permissions to a user to run a program/file with the permissions of the file group permissions to become member of that group to execute the file. In simple words users will get file Group’s permissions when executing a Folder/file/program/command.