Guardian Application Conversion Guide

New Process Identifiers
Conversion Concepts
2–14 096047 Tandem Computers Incorporated
Process Descriptors A process descriptor is a special case of a D-series process file name. It replaces the
process ID or CRTPID for returning the identity of a process from a procedure call
(such as PROCESS_CREATE_). It always contains a node name and a sequence
number as well as either a process name or a dollar sign and CPU/PIN designation. A
process descriptor never contains a qualifier.
The format for a process descriptor for a named process or named process pair is:
node-name . process-name : sequence-number
The format for a process descriptor for an unnamed process is:
node-name .$: cpu : pin : sequence-number
If necessary, you can use the FILENAME_EDIT_ procedure to remove the node name
or sequence number from the string.
Process Handles The D-series process handle replaces the C-series four-word process ID or CRTPID for
passing information to a Guardian procedure. You use a process handle in process-
control Guardian procedures such as PROCESS_STOP_ and PROCESS_ACTIVATE_
or in information procedures such as PROCESS_GETINFO_ . (Process-control
procedures operate only on processes and not on files; you use a process file name for
procedures that operate on files.)
A process handle is a 10-word (20-byte) structure that identifies a single named or
unnamed process. For a named process pair, a process handle identifies each specific
member of the pair.
Note The format for a process handle is subject to change in future releases. Your application should not try to
extract information (such as a CPU number or PIN) from a process handle except by using a Guardian
procedure such as PROCESSHANDLE_DECOMPOSE_.
A process handle contains the following information about a process:
A PIN identifies the process within a specific CPU. A D-series PIN ranges from 0
through the maximum number supported by the system (except for PIN 255,
which is never used in a process handle).
A CPU number identifies the CPU in which the process is running. The CPU
number ranges from 0 through 15.
A node (or system) number identifies the node within a network. The number
ranges from 0 through 254.
A verifier or sequence number allows the system to uniquely identify a process
over its lifetime.