1. Intro to VM
CP & CMS
5/25/2019

2. Environments CP CMS The real O/S running the mainframe
Commands control virtual machine
CMS
A “shell” & “mini O/S”
Has page 0 reserved storage, same as CP
Can process virtual interrupts
Virtual privileged mode
File system
Commands for file system & more
© D. J. Foreman, 5/25/2019

3. Environmental hints RUNNING MORE … will auto-clear in 30 seconds
data pending for display
must clear the screen to see it
HOLDING must click on the “clear” button
CP READ commands go directly to CP
VM READ commands go to CMS
You may “pass” commands to CP via “CP” prefix
E.g.; CP Q TIME
© D. J. Foreman, 5/25/2019

4. CMS structure Minidisk - Disk storage
Access mode - letter (A-Z) assigned to a disk
Search order – like “path” in Windows or Linux but only contains access mode letters
“flat” file system
No “folders”
Files have a name, a type and a mode-letter
E.g.; sos assemble a
Default mode-letter is “A”
© D. J. Foreman, 5/25/2019

5. More on structure Search order
z/a means search ‘z’ as if it was at end of ‘a’
R/O disk is read only
RW disk is read & write
Shared file system (SFS) (not available for 552)
Hierarchical file system
Extends CMS file system
Sub-directories
Multi-user accessible
© D. J. Foreman, 5/25/2019

6. Bingtjw 3270 login screen
© D. J. Foreman, 5/25/2019

7. Logging in CMS shell auto-starts PROFILE EXEC – Rexx script runs
Connects to Foreman’s 999 as your “Z” disk
Sets up for printing
Screen captures
Files
Runs PROFILE2 EXEC (also in Rexx)
Sets up colors
Sets up F-keys
F2 = retrieve
F3 = clear screen
Asks for re-boot into Linux
© D. J. Foreman, 5/25/2019

8. Some basic CP commands Ipl like BIOS, loads an O/S
I CMS
I 222 (to “boot” your SOS program)
Query - ask about virtual environment
SET - change virtual environment
Begin - resumes execution
Trace - instruction tracing, like gdb in Linux
Display - show RAM, PSW, register content
Commands are NOT case sensitive
© D. J. Foreman, 5/25/2019

9. CMS Command Syntax Command [Operands] [( options]
Commands have a “minimal truncation”
The ( is required preceding any options
Commands are NOT case sensitive
© D. J. Foreman, 5/25/2019

10. Some basic CMS commands
HELP - activities & specific commands
ACcess - put a disk in the search order
Query - file system & other info
Search - lists disks in search order
Disk - lists virtual disks
Time
SET - file system & environment
SENDFile Fn Ft to user at loc (SMTP
FILEList
hx - halts execution of a CMS program
© D. J. Foreman, 5/25/2019

11. More CMS commands Load - links elements of a program
Genmod - makes a RAM image of a program
COPYfile - copies files
Print - send a file to the output queue - should be available via Pharos
TELL - sends a message to another user
#CP - forces command directly to CP - bypasses any outstanding “read” - never seen by user’s program
© D. J. Foreman, 5/25/2019

12. XEDIT Built into CMS Command driven Expandable via REXX programs
See Z-disk for examples
Tailorable elements
Colors
Layout
© D. J. Foreman, 5/25/2019

13. Some Xedit commands Commands operate from “current line” to end
f, b scroll forward or back
.name scroll to named line
top scroll to top of file
bot scroll to bottom of screen
/string locate “string”
c/s1/s2 change s1 to s2
c/s1/s2/* change s1 to s2 on all lines
c/s1/s2/3 4 change s1 to s2 on 3 lines for up to 4 occurrences per line
© D. J. Foreman, 5/25/2019

14. Xedit “line” commands .name names a line c copy
cc copy multiple lines (must be paired)
a after
b before
© D. J. Foreman, 5/25/2019

15. REXX Similar to many procedural languages All variables are strings
PL/1
Perl
Pascal
All variables are strings
Built-in conversion as needed
Text parsing function
© D. J. Foreman, 5/25/2019

16. Special setup instructions for advanced O/S class
Format I
Creates the CMS file system for this disk
Puts disk in search order as disk “I”
Format 222 I 4 (recomp
Reserves 1 cylinder for SAL
You only need to do this ONE TIME
© D. J. Foreman, 5/25/2019