RFC 121 (rfc121) - Page 1 of 13

Network on-line operators

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Network Working Group                                     M. Krilanovich
Request for Comments: 121                    Computer Research Lab, UCSB
NIC: 5833                                                  21 April 1971


                       NETWORK ON-LINE OPERATORS

PREFACE

   The operators described in this document have been implemented within
   UCSB's On-Line System and make the Network (via the NCP) accessible
   to On-Line System users.

   A set of operators is provided to facilitate the use of the Network
   by On-Line System users.  The operators are defined on LVL I on
   system 'NET', and serve an an interface between the users and the
   Network Control Program (NCP), which supervises all Network
   operations at this site.

   A concept fundamental to On-Line System Network operations is that of
   a completion code variable.  Associated with each socket that is not
   in the closed state is a unique variable, called a completion code
   variable.  This variable serves two purpose: it identifies the local
   socket referenced, and upon completion of the operation it contains a
   completion code to indicate the outcome of the operation to the user.
   It may be used at any time for any purpose other than Network
   operations.  Its value at the beginning of a Network operation is
   immaterial rather it is the variable itself that is important.  In
   all Network operations, whenever a completion code variable is called
   for, the only acceptable type variable is a LO storage location,
   either case 1 or case 2.

   In those operations requiring a socket to be specified by its socket
   identifier, the following format is used: the site number of UCSB is
   always used for local sockets, and so this item is never specified.
   The site number of a foreign socket, if specified, must be a positive
   integer or a LO storage location, and must be less then 256 in value.
   If not specified, the site number of a foreign socket will default to
   the site number of UCSB.  A socket number is specified as an integer,
   either unsigned, in which case it is assumed to be positive, or with
   an explicit minus sign, or a LO storage location, of any value.
   Negative socket numbers are represented internally in two's
   complement form and therefore for the purpose of the gender of a
   socket, a socket number is even or odd according to whether its
   absolute value is even or odd, respectively.






Krilanovich
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