The operator may enter RSCS commands descrited in Figure 2 at the RSCS virtual machine console. A subset of the co •• and language .ay te entered by operators of remote stations.
command
Name Function BACKSPAC Restarts or repositions in a backward direction the file
currently being transmitted.
CHANGE Alters one or more attributes of a file owned by RSCS. CMD Controls certain functions performed by a remote system, or controls the logging of I/O activity on a specified
link.
DEFINE Temporarily adds a new link definition to the RSCS link
table or temporarily redefines an existing link.
DELETE Temporarily deletes a link definition from the RSCS link
table. DISCONN Places RSCS in disconnect mode and optionally directs
output to another virtual machine.
DRAIN Deactivates an active communication link. FLUSH Discontinues processing the current file on the specified
link.
FREE Resumes transmission on a communication link previously
in HOLD status. FWDSPACE Repositions the file currently being transmitted in a
forward direction. HOLD Suspends file transmission on an active link without
deactivating the line. MSG Sends a message to a local or remote station. ORDER Reorders files enqueued on a specific link. PURGE Removes all or specified files from a link. QUERY Requests system information for a link, a file, or for
the system in general. START Activates a specified communication link.
TRACE Monitors line activity on a specified link.
Figure 2. RSCS Commands and Functions VM/370 CP AND CMS COMMANDS FOR RSCS The VM/370 CP TAG and SPOOL commands specify a device to he spooled and
to associate a destination location identifier (locid) with that device. SPOOL directs the file to the RSCS virtual machine. The CP CLCSE 3-6 IBM VM/370: System Logic and Problem Determination--Volume 3

command or the CMS PRINT or PUNCH commands close the file and transfer
it to the RSCS virtual machine. Data specified by the CP TAG command
transmitted across the RSCS network. When
to be transmitted to a remote station via
operand takes the following format:
linkid [userid] [priority]
controls processing of files
a V"/370 user creates a file RSeS, the TAG command text
linkid is the location identifier of the link on which the file
is to be transmitted.
userid is the remote virtual machine that is to receive the
file.
priority is the requested transmission priority (a decimal number 0-99, default The lower numbers have higher
priorities.
Also, ·the CP SPOOL comlRand directs files to the R ses virtual machine. See the publication For details on how to use the ep TAG and SpeeL commands tc control RSCS network functions, see the When Rses handles files being transmitted across the network, the Rses
control program (line driver tasks) issues CP DIAGNOSE instructions.
The DIAGNOSE instruction is the method of communication between a
virtual machine and CP. In VM/370, the machine-coded format for the DIAGNOSE instruction is: 83
rx
ry
Code
Figure
functions
issued.
o 7 8 11 12 15 16
83 rx ry
l DIAGNOSE operation code
User-specified register number
User-specified register number
31
Code
Hexadecimal value that selects a particular ep function, 3 lists
ef those
the DIAGNOSE function codes used
codes, and the Rses modules from
by RSCS, which they
the
are
The RSCS Control Program
Rses is a contrel program composed of a multitasking supervisor and
multiple tasks, which are controlled by the supervisor.
Rses Introduction 3-7