создавать и администрировать файлы SCCS (РАЗРАБОТКА) (create and administer SCCS files (DEVELOPMENT))
Описание (Description)
The admin utility shall create new SCCS files or change
parameters of existing ones. If a named file does not exist, it
shall be created, and its parameters shall be initialized
according to the specified options. Parameters not initialized
by an option shall be assigned a default value. If a named file
does exist, parameters corresponding to specified options shall
be changed, and other parameters shall be left as is.
All SCCS filenames supplied by the application shall be of the
form s.filename. New SCCS files shall be given read-only
permission mode. Write permission in the parent directory is
required to create a file. All writing done by admin shall be to
a temporary x-file, named x.filename (see get(1p)) created with
read-only mode if admin is creating a new SCCS file, or created
with the same mode as that of the SCCS file if the file already
exists. After successful execution of admin, the SCCS file shall
be removed (if it exists), and the x-file shall be renamed with
the name of the SCCS file. This ensures that changes are made to
the SCCS file only if no errors occur.
The admin utility shall also use a transient lock file (named
z.filename), which is used to prevent simultaneous updates to the
SCCS file; see get(1p).
