Table of Contents
c.pfcopy
Case Study
We will use the group file compass
which we created on CYBIS/R1 as our example.
Virtual "Write Protect"
The ability to write changes is disabled by default.
The only way to initiate a transfer that writes on the target is to use the -W
or --write
switches.
Understanding the Syntax
Before we do anything, let's examine the syntax of the copy command:
cdc.io c.pfcopy -I "E:\Emulation\TH.CybisRelease1\Disks" -O "E:\Emulation\CybisRelease2.Prod\disks" -f *.compass@* -t system.xcompass@gen01
The cluster path specifications (-I and -O options) signify the same -Input and -Ooutput clusters used elsewhere in these tutorials. The other options are important to understand before proceeding.
The -from and -to specifiers are called Cluster Object
specifiers. They generally describe the origin file and the target file parameters. A deeper tutorial on how to use these, and Cluster Path
specifiers may be found in other tutorials.
The source file compass
(Described using the -f
option):
- a
group
file (we know this empirically) - 3-parts in length (we know this empirically)
- will come from master file
packx
(we know this empirically) - will come from account
acctx
(we know this empirically) - we don't know the name of the Master File on which it resides (we don't really need to)
The Asterisk ''*'' Placeholders
We signify that we don't care what the source account is, or what the source master file is, by use of the *
placeholders.
The target file xcompass
(Described using the -t
option):
- β¦ will still be a
group
file - 3-parts in length (cannot be changed)
- we want the file to be contained in account
system
- we want the file to reside on Master File
gen01
- the file does NOT already exist (it will be created, and added to account
system
)
Warning
If the target file already exists, it MUST be the same size as the source file. If the target file already exists, and is not in the account specified on the cluter object specification
, the command will abort.
Unless You Know What You're Doing
Under rare circumstances, it is permissible to perform transfers between systems while they are active (meaning, NOS and PLATO/CYBIS are running). The practice is strongly discouraged, especially if files are being created or deleted. If transfers involve existing master files with existing files of the same size and type, there might be no need to take NOS down completely but you are strongly encouraged to ensure that PLATO/CYBIS is not running. Stopping and Starting PLATO/CYBIS is relatively quick.
To perform a dry-run (the default) simply press βenterβ. This will fail because in performing the simulated writes, at some point, the function will need to see that the space has been successfully allocated before the simulated copy can take place. All other accounting structures must be complete or the write operation cannot succeed.
Using lesson operator
we now see the file:
Advanced Functionality
The c.pfcopy
subcommand has much more powerful (and therefore, dangerous) features. Learn More about the advanced features.