CHANGELOG


CHANGELOG

     Changes the user logging file without stopping or
interrupting the logging process. (CM)

SYNTAX

     CHANGELOG LOGID [;DEV=DEVICE]


PARAMETERS

LOGID               NAME OF THE CURRENTLY ACTIVE USER LOGGING PROCESS.
THIS NAME MAY CONTAIN FROM ONE TO EIGHT ALPHANUMERIC
CHARACTERS, BEGINNING WITH AN ALPHABETIC CHARACTER.

DEVICE NAME OF THE DEVICE ON WHICH THE NEW LOGGING FILE IS
TO BE CREATED. THE DEVICE MAY EITHER DISC OR TAPE.
DEFAULT IS DISC.


OPERATION

     THIS COMMAND PERMITS THE USER TO CHANGE THE ACTIVE LOGGING
FILE WITHOUT STOPPING THE LOGGING PROCESS WITH THE LOG
LOGID, STOP COMMAND. BY SPECIFYING A DEVICE, YOU MAY SWITCH
THE LOGGING FILE FROM ONE DEVICE TO ANOTHER, REGARDLESS OF
THE DEVICE ON WHICH THE LOGGING FILE WAS CREATED. IF YOU
HAVE ENABLED AUTOMATIC LOGGING WITH THE ALTLOG OR GETLOG
COMMAND, HOWEVER, THE ONLY DEVICE AVAILABLE FOR LOGGING IS
THE DEFAULT, DISC.

IF THE CHANGELOG COMMAND IS VALID, THE SYSTEM WRITES A
CHANGELOG RECORD TO THE END OF THE CURRENT LOGGING FILE AND
CLOSES THE FILE. IT THEN OPENS A NEW LOGGING FILE WHOSE
CHARACTERISTICS ARE IDENTICAL TO THOSE OF THE PRECEDING FILE
AND MAKES THE NEW FILE PERMANENT. IF THE SYSTEM IS UNABLE
TO OPEN A NEW FILE OF THE SAME SIZE, IT WILL TRY TO OPEN A
NEW FILE HALF THE SIZE OF THE OLD FILE. IT WILL REPEAT THIS
PROCESS UNTIL A NEW FILE IS OPENED SUCCESSFULLY, OR UNTIL
THE SIZE IS LESS THAN 256 RECORDS. IN THE SECOND CASE, USER
LOGGING TERMINATES.

IF THE SYSTEM OPENS A NEW LOG FILE, IT WILL IMMEDIATELY
WRITE A CHANGELOG RECORD TO THE NEW FILE. THE CHANGELOG
RECORD POSTED TO THE OLD LOGGING FILE CONTAINS THE FULLY
QUALIFIED IDENTIFIER OF THE NEW LOGGING FILE. A
CORRESPONDING CHANGELOG RECORD WRITTEN TO THE NEW FILE WILL
CONTAIN THE FULLY QUALIFIED IDENTIFIER OF THE OLD LOGGING
FILE. CHANGELOG RECORDS WILL ALSO CONTAIN THE DEVICE TYPE
OF THE LOGGING FILE TO WHICH THE CHANGELOG REFERS.

THE FOLLOWING MESSAGES WILL BE DISPLAYED ON THE $STDLIST TO
CONFIRM A SUCCESSFUL CHANGE

LOG FILE FOR LOGID AAA HAS BEEN CHANGED FROM A001.PUB.SYS
TO A002.PUB.SYS (ULOGMSG 38)

IF THE NEW LOGGING FILE IS A SERIAL FILE, A MESSAGE WILL APPEAR ON
THE CONSOLE ADVISING THE OPERATOR TO MOUNT THE NEW LOG FILE

MOUNT NEW TAPE VOLUME FOR CHANGELOG OF LOGID AAA (ULOGMSG 40).

NORMALLY WHEN A USER LOGGING FILE IS FULL, THE SYSTEM TERMINATES
THE LOGGING PROCESS AND DISPLAYS AN APPROPRIATE MESSAGE.

HOWEVER, BY SPECIFYING THE AUTO PARAMETER IN A GETLOG OR ALTLOG
COMMAND, YOU WILL ENABLE AN AUTOMATIC CHANGELOG, THEREBY FREEING
YOURSELF OF THE NEED TO ISSUE THE CHANGELOG COMMAND MANUALLY.
REFER TO THE ALTLOG AND GETLOG COMMANDS.

IN ORDER TO USE CHANGELOG (MANUALLY OR AUTOMATICALLY), YOU MUST
END THE FIRST USER LOGGING FILE NAME WITH THE NUMERIC CHARACTERS
001 (FOR EXAMPLE, FNAME001). THIS ESTABLISHES A NAMING CONVENTION
THAT WORKS IN CONJUNCTION WITH THE FILE SET NUMBER TO GENERATE
SEQUENTIAL FILE NAMES INDEPENDENTLY. NEW FILE NAMES WILL CONSIST
OF THE FILE NAME ROOT (FNAME) PLUS THE NEXT SEQUENTIAL INCREMENT OF
THE LAST THREE DIGITS

CURRENT FILE NEXT FILE

TEST001 TEST002
TEST002 TEST003
... ...
TEST998 TEST999
TEST999 TEST000

THE LOGGING PROCESS OPENS FILES, AND AUTOMATICALLY NAMES THEM WITH
THE NEXT SEQUENTIAL NUMBER, UP TO A MAXIMUM OF 999. THEREAFTER, THE
NUMBERING SEQUENCE WILL RESET TO 000 AND BEGIN INCREMENTING ALL
OVER AGAIN.

AUTOMATIC LOGGING WITH THE CHANGELOG COMMAND IS AVAILABLE ONLY FOR
DISK FILES.

NOTE

THE LOGGING PROCESS SPECIFIED BY LOGID MUST BE CURRENTLY ACTIVE. IF THE
LOGGING PROCESS IS IN ANOTHER STATE, SUCH AS RECOVERING, STOP,
INITIALIZING, OR IF THE LOGGING PROCESS HAS ANOTHER CHANGELOG PENDING,
THE COMMAND WILL TERMINATE IN AN ERROR STATE. THE ALTLOG COMMAND
PERMITS CHANGING THE LOG FILE FOR AN INACTIVE LOGGING PROCESS. ALTLOG,
HOWEVER, DOES NOT PROVIDE A WAY TO LINK LOG FILES INTO A SET.

THIS COMMAND MAY BE ISSUED FROM A SESSION, JOB, IN BREAK, OR
FROM A PROGRAM. PRESSING [BREAK] HAS NO EFFECT ON THIS
COMMAND. IT IS AVAILABLE ONLY TO THE CREATOR OF THE LOGID
AND REQUIRES SYSTEM SUPERVISOR (OP) OR USER LOGGING (LG)
CAPABILITY.


EXAMPLE(S)

IF YOU ARE RUNNING A LOGGING PROCESS WITH A LOGID OF KATHY, LOGGING TO
A LOGFILE, KLOG002, WITHOUT INTERRUPTING THE LOGGING PROCESS, ENTER:

CHANGELOG KATHY

ADDITIONAL INFORMATION

COMMANDS:   LISTLOG, SHOWLOGSTATUS, GETLOG, ALTLOG

MANUALS : User Logging Programmer's Guide (32650-60012)