Locking Your Shared Files

If you have granted another user write authority to one of your files, or if you have write authority on another user's files, you need to understand how CMS handles multiple users working with the same file.

You do not usually need to worry about locking your files and directories. CMS prevents other users from changing a shared file while commands are processed. For example, another user could not make changes to a file at the same time you are copying or renaming it. Files are also locked automatically when you XEDIT them.

You may, however, want to lock a file or directory if you need to complete a series of commands. For example, you might need to copy a file, XEDIT and change the copy, and compare the two files. In such a situation, a lock on the file or directory prevents other users with authority from changing the file before you complete your work.

Note.

If you logged off after the last section and have just logged on again, you will need to re-enter some commands before we continue.

If you entered the following commands at the beginning of this chapter

set filepool vmsysu:
acc . a
acc 191 m

enter them again now to set up SFS storage for users who usually store their files on a minidisk and to re-establish the original CMS session.

All users who logged off will need to re-access the LEISURE and SUMMER directories. Enter:

acc .leisure b
acc .leisure.summer c

Now you are ready to continue.