TAA Tools

 CHKOBJDMG       CHECK OBJECT DAMAGE                    TAALIBF

 The Check  Object Damage command  checks all of  the objects in  one or
 all libraries for damage.

 The check occurs by saving each object to a save file in QTEMP.

 A typical command is entered as:

         CHKOBJDMG   LIB(xxxxx)

 A report is output to the spooled file OBJDMG.  Exceptions are noted:

   **   If the  object is already  marked as damaged,  an exception line
        is printed.

   **   If  the  object cannot  be successfully  saved, an  exception is
        printed.  The most typical  error found will be that  the object
        is locked  and cannot be saved.   To determine  the actual cause
        that  the  object  could  not be  saved,  the  job  log  must be
        reviewed.  The CPD3761  message indicates the locked  condition.

        If damage is  detected by the save command, the  object will now
        be  marked  as damaged.    Another execution  of  CHKOBJDMG will
        show  the  object  as  damaged  in  the  printed  listing.     A
        diagnostic in the job log will note the damage condition.

 Successfully executing the  CHKOBJDMG command does not ensure  that any
 undetected damage exists.  See the Restrictions section.

 The objects  are saved one  at a time to  a save file in  QTEMP.  There
 must  be enough room  in the save  file to hold  the largest object you
 will be checking.   If you  have large data  base objects, you  may not
 have  enough room  to  save them  to the  save  file.   If  so, specify
 CHKPF(*NO) to avoid checking these objects.

 The  checking that  occurs by  CHKOBJDMG only ensures  that all  of the
 pages of an object exist to be  saved.  This is a sanity test and  does
 not ensure that the bytes will perform a valid function.

 Data  base files  take  up the  most  amount of  storage  on a  typical
 system  and can  have damage  within  the data  portion of  the object.
 The CHKOBJDMG  command will  detect  certain damage,  but it  will  not
 detect damage  in  the data  portion of  the object.   To  do a  better
 validation  of data  base files,  you should  consider  the use  of the
 VALDBF tool (includes the VALMNYDBF command).

 VALMNYDBF  will cause all physical members in  a file, a library or all
 user libraries to  be processed.   The processing includes reading  all
 of  the records,  checking for  valid numeric  data (if  there  are any
 externally  described numeric fields) and checking  fields based on any
 DDS validity checking specifications (e.g.  RANGE).

 If you suspect  damage on your  system, a reasonable  test would be  to
 use CHKOBJDMG  with CHKPF(*NO)  and VALMNYDBF  for all  user libraries.
 Note  that both  of  these functions  are very  long running.    If you
 suspect damage in  a library,  both commands  could be  used against  a
 specific library.

 Libraries and objects not saved
 -------------------------------

 The  following  libraries  cannot  be  specified.     If  LIB(*ALL)  is
 specified, they are bypassed.

        QSYS
        QDOCx
        QSPL

 The following  object types cannot be  saved by SAVOBJ.  If  found in a
 library, they are bypassed:

       *DOC
       *FLR
       *PRDLOD
       *PRDDFN

 Command parameters                                    *CMD
 ------------------

    LIB           The  library to be checked.   *ALL may be specified to
                  check  all   libraries.     See   the  discussion   of
                  libraries and  objects not saved.  You  must have *USE
                  authority  to  the  TAADSPADP  authorization  list  to
                  specify *ALL.

    CHKPF         A *YES/*NO value  for whether  data base files  should
                  be  checked by  saving  them.   *YES  does not  ensure
                  that  the file  contains valid data.   See  the VALDBF
                  TAA tool to check the file.

                  If  *YES  is  specified,  you  must  have   sufficient
                  storage  space on  your  system  to save  the  largest
                  file in the library.

 Restrictions
 ------------

 Checking  for  damage by  performing  a  save does  not  check for  all
 potential  damage  conditions.   It performs  a  sanity check  that all
 objects can be saved.

 It  is  possible for  the  system  to  save  undetected  damage.    For
 example:

   **   If a  program object  has been damaged  so that  the instruction
        stream  cannot be executed  (e.g.   invalid machine operations),
        this  will  not   be  detected   unless  the  instructions   are
        executed.

   **   If a data  base object contains data that is  incorrect based on
        the  DDS description of  the data (e.g.   numeric fields  do not
        contain valid  digits), the  error will  not be  detected  until
        the field  is  used in  a numeric  operation.   The TAA  command
        VALMNYDBF will find this type of error.

   **   In  front of  every  data  base record  is  a byte  used  by the
        system  to determine  if the record  has been deleted.   If this
        byte contains an  invalid bit combination, the  damage condition
        will  not  be  reported until  the  record  is  read by  a  data
        management  function.   The  save  function picks  up  blocks of
        data and  does  not  check  the leading  byte.    The  VALMNYDBF
        command will find this type of damage.

   **   Logical  file  objects  are  checked for  damage,  but  not  the
        access  paths.  Logical  file access  paths are only  saved with
        the based  on physical  file if  specifically requested  on  the
        save command (they are not saved in the tool).

 See also the discussion of libraries and objects not saved.

 Prerequisites
 -------------

 The following TAA Tools must be on your system:

      DSPOBJDA     DSPOBJD with adopt (part of DSPADP tool)
      EDTVAR       Edit variable
      RTVSPCAUT    Retrieve special authority
      RTVSYSVAL3   Retrieve system value 3
      SNDCOMPMSG   Send completion message
      SNDESCMSG    Send escape message
      SNDSTSMSG    Send status message

 Implementation
 --------------

 None, the tool is ready to use.

 Objects used by the tool
 ------------------------

    Object        Type        Attribute      Src member    Src file
    ------        ----        ---------      ----------    ----------

    CHKOBJDMG     *CMD                       TAALIBF       QATTCMD
    TAALIBFC      *PGM           CLP         TAALIBFC      QATTCL

Added to TAA Productivity Tools April 1, 1995


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Last modified on November 19, 2014 © 1995, 2014 - TAA Tools, Inc.