UIC

   A UIC is a user identification code that can be in either numeric
   or named format. When a DCL command requires a UIC specification,
   you can specify either format. However, the system converts all
   UICs to numeric format when determining a user's access to a data
   resource.

   A UIC in numeric format consists of a group number and a member
   number in the format:

      [group,member]

   where:

   group  is an octal number in the range 0 through 37776
          representing the group number.
   member is an octal number in the range 0 through 37776
          representing the member number.

   The square brackets are required in the UIC specification. You
   can also omit leading zeros when specifying group and member
   numbers.

   A UIC in named format consists of a member identifier and
   optionally, a group identifier, as shown in either of the
   following:

      [member]

      [group,member]

   The group and member identifiers can each contain up to 31
   alphanumeric characters and must contain at least one alphabetic
   character. The names can include the characters A through Z,
   dollar signs ($) underscores (_), and the numbers 0 through 9.
   The brackets are required in the UIC specification.

   The member number is unique for each user on the system, and is
   equivalent to the user's numeric UIC (including both the group
   and the member numbers). The group identifier is equivalent to
   only the group portion of the UIC.

   For additional information on specifying UICs, refer to the
   VSI OpenVMS Guide to System Security.