These THEOS commands are used together to define and set up system parameters such as time, date, memory allocation, multi-user operation, single-user operation, system history, etc. The SET com-mand will be discussed first followed by START and then STOP.
THE SET COMMAND
This command allows such functions as time, date, and memory allocation to be changed as the needs of the system dictate. The format of the SET command is:
SET parameter status
Parameter is the function altered by the command. Status is the condition to which the parameter is changed.
More parameters are available in THEOS than those discussed here. We have limited our discussion to those parameters most useful in day-to-day system operation.
Certain privilege levels may be required to set some parameters.
Parameter Function
DATE mm/dd/yy Permits changing of the system date. Requires a privilege level of 5.
RDYMSG Permits the on-screen display of the system ready message which consists of the return code, current system time and elapsed time of function executed.
TIME hh:mm:ss Permits changing of the system clock. Requires a privilege of 5.
MEMORY Allocates memory partitions for multi-user opera-tion and memory size. Requires a privilege level of 5.
Figure 4.33. SET parameters and their functions
The following entry illustrates how SET can be used to change the system date:
>SET DATE 12/29/84<RETURN>
THEOS will reset the system date to December 29, 1984.
SET can be used as shown below to change the status of the system ready message:
>SET RDYMSG ON <RETURN >or SET RDYMSG OFF <RETURN>
The purpose of the system ready message is to display the follow-ing information:
• the system retu rn code
• the current system time
• the time required to execute the last THEOS command typed
The return code is a number THEOS uses to determine whether or not commands have been executed without error. A return code of 0 indicates that a command operation was successfully completed. Other return codes will be discussed in chapter 6. The ready message informa-tion can be most useful when testing THEOS programs or EXECS that use the return code to display error messages.
To set anew system time type:
>SET TIME 15 24<RETURN>
Enter any char to set time to (15:24:00) <RETURN>
The current month and year are displayed along with the new time entry. Rather than automatically setting the time as soon as
<RETURN> is pressed, the prompt provided by THEOS allows setting the exact time when a character is entered. Note that THEOS uses a twenty-four hour time clock.
THE SET MEMORY COMMAND
The SET MEMORY command is vitally important since it allo-cates memory partitions for multi-user operation. A memory partition is a portion of the total system memory assigned to each THEOS user.
This partition allows the user enough memory to run application software and share the common microprocessor. Memory partitions
142 THEOS User's Handbook
must be allocated in ascending order and deallocated in descending order. When the multi-user version of THEOS is booted, there is only one active memory partition.
Most multi-user THEOS systems are supplied with a minimum of 256K RAM which is sufficient for five users (each with 45K) and a printing spooler shared among all users. Before multi-user operation can begin, memory must be allocated to each user. Conversely, if in multi-user mode, memory must be deallocated before single-user operation can begin. To clarify, let's use an example.
In a system with 256K RAM, when the system is first booted one memory partition is automatically activated. This partition allocates approximately 45K for the user and 20K for the THEOS nucleus. To prepare for multi-user operation and allocate memory for user parti-tions two through five, type:
>SET MEM 2 1 1<RETURN>
>SET MEM 3 1 2<RETURN>
>SET MEM 4 1 3<RETURN>
>SET MEM 5 1 4<RETURN>
To prepare for single-user operation and deallocate the available mernory type:
>SET MEM 5 1 4<RETURN>
>SET MEM 4 1 3<RETURN>
>SET MEM 3 1 2<RETURN>
>SET MEM 2 1 1<RETURN>
Enter the commands detailed in this section from the main termi-nal or from the termitermi-nal attached to port one.
The START and STOP Commands
These commands are used together primarily to activate and deactivate user partitions allocated by the SET MEMORY command.
The START command is used to activate the memory partitions.
U sing the example above, to activate the memory partitions for multi-user operation type:
~ >START2<RETURN>
>START 3<RETURN>
>START 4<RETURN>
>START S<RETURN>
~ ~
When the START command is executed, the user whose partition was most recently activated is prompted on the screen to "Logon please:". If that particular terminal has not yet been turned on, it may be necessary to enter a <RETURN> after start-up in order for the logon message to appear. Once the logon messages appear on the terminals, the system is ready for multi-user operation.
The STOP command is used to deactivate the memory partitions.
In order to deactivate the multi-user system initialized in our examples, type:
>STOPS<RETURN>
>STOP4<RETURN>
>STOP3<RETURN>
>STOP2<RETURN>
This command cannot be used unless a user has logged off. When a user on a particular terminal has logged off and the terminal is still active, the message: **Partition has been stopped!** appears on the screen. This informs any prospective users that the system is not available for multi-user operation.
The STOP command only stops the operation of a memory partition. It does not deallocate the memory. Deallocation is accomp-lished by the SET MEMORY command.
SUMMARY
The SET command is used to change certain parameters such as time, date, and memory allocation for multi-user operation. The START and STOP commands are necessary in order to activate and deactivate memory partitions to start and stop multi-user operation.
These functions must be performed from the terminal attached to port, one on the system.
144 THEOS User's Handbook
Session 19: The SHOW Command
The SHOW command provides THEOSusers with the ability to display the status of certain system parameters. The format of the SHOW command is:
SHOW parameter
Parameter Function
BANK Displays the available memory banks and their sizes.
DISK Displays the status of all currently attached disks or, when specified, a particular disk.
MEMORY Displays the current allocation and usage of memory (RAM).
PRIVLEV Displays the privilege level of the currently logged user.
RDYMSG Displays status (on or off) of the ready message switch.
SERIAL Displays the serial number of the THEOS operat-ing system in use.
TIME Displays the current system time and date.
USERS Displays information about any users currently logged onto the system.
WHO Displays the account name of the currently logged account.
Figure 4.34. Show parameters
The following entry illustrates the use of the SHOW BANK command'
>SHOW BANK<RETURN>
>
ReQ-ion
Low
Hiah SizeNUCLEUS
OOOOH 3FF4H 16363Bank/#OO 3FF5H FF7FH 49035 Bank #01 4000H FFFFH -q9152 Bank #02 4000H FFFFH 49152 Bank 103 4000H FFFFH 49152 Bank #04 4000H 9036H 20537
The data of most interest to us here is the bank number and the size of each bank. This command was executed on a THEOS system with 256K RAM. The information displayed is an indication of how the memory might be allocated in a THEOS system with five users and a print spooler.
r
The SHOW DISK command can be executed as follows:
>SH DI<RETURN>
Label: "HARDISK1",
Archived to disk "TEST "on 05/19/85 10:44 Capacity: 1~,5~~K bytes (303-6-32),
Available: 7,144K bytes (49~),
LarQest area: 7,109K bytes, 830 files in use (out of 1,944)
Five lines of information about the disk are displayed.
• Directory label
• Disk capacity in K bytes, number of cylinders, number of heads, number of sectors per track
• Amount of storage available in K bytes and percentage
• Largest amount of contiguous disk space
• Number of files currently in the disk directory, number of entries allocated.
In addition the SHOW DISK command checks for proper disk space allocation and reports any misallocated space with an error message displayed on the line following the number of directory entries allocated. Misallocations are indicated by a + or - number in K bytes.
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Negative misallocation indicates that more space has been allo-cated for file storage than is actually being used. Positive misallocation indicates that less space has been allocated than actually in use. These conditions are not normal and should be corrected before the system is used further. Negative misallocation is usually a result of improper closing of a file due to a bug in a software package or a power failure during system operation preventing proper exiting of a program. The positive misallocation is the more serious condition of two because it may mean that two files are sharing the same disk space and that one or both contain invalid data. See chapter 5 for instructions on how to correct misallocations.
The following example illustrates usage of the SHOW MEMORY command:
>SH MEM<RETURN>
Bank MEMLO MEMMX MEMHI SP--- PC--- Size Routine
OOOOH 3FF4H 16373 NUCLEUS
1 * 0 3FF5H FF7FH FB09H FB02H 4C01 H 4-9035. SHOW USER2
>
This command is used to display the current memory allocation.
In this example there is only one user on the system. When this command is executed in a multi-user environment, information about each user is obtained. The information displayed is port, bank, size, routine, and user. Port references the port on the computer in which the terminal is plugged. Bank is the number of the memory bank contain-ing the RAM for that user. Size is the amount of memory available to that user. Routine is the THEOS command currently being executed by that user. In this case the command is SHOW. Username is the account name of the currently logged user. The asterisk indicates the user executing the SHOW command.
As shown in the following example, the SHOW PRIVLE com-mand indicates the privilege level of the currently logged user.
>SHOW PRIVLE<RETURN>
PRIVLEV =5
>
The on/ off status of the ready message switch is displayed by the SHOW RDYMSG command as shown below:
>SHOW RDYMSG<RETURN>
RDYMSG=ON
The SHOW SERIAL command displays the serial number of the THEOS system in use as shown in the following example:
>SHOW SERIAL<RETURN>
SERIAL =00-00000 (whatever your serial number is)
As shown below the SHOW TIME command displays the current date and time:
>SHOW TIME<RETURN>
hh:mm:ss day of week, month/date, current year
>
The SHOW USERS command displays information about the currently logged users such as the port number of their terminal, their account name, and date and time of logon. In the following example, one user, USER3, is currently logged onto the system.
148 THEOS User's Handbook
>SHOW USERS<RETURN>
Port Username Log-Date Log-Ti me 1 * USER3 01/01/84 11 :11 :31
>
The SHOW WHO command displays the account name of the currently logged account.
>SHOW WHO<RETURN>
USER3 Logon 11 :11 :31 01/01/84
>
This command is useful because it is possible to forget the account name of the currently logged account. By typing this command you are instantly reminded of the account name under which you are logged on, as well as the time and date of the logon.
SUMMARY
The SHOW command is useful for displaying the status of certain THEOS parameters. It can be executed at any time from the THEOS prompt. The most commonly used parameters were examined in this tutorial.