Invokes the  VMS  Image  File  Patch Utility  (PATCH)  to  patch  an
  executable  image,  shareable  image, or device driver image.  For a
  complete functional description of the Patch Utility, including more
  information  about  the  PATCH  command  and its qualifiers, see the
  VMS Patch Utility Manual.

  Format:

    PATCH  file-spec

Additional information available:

ParametersCommand QualifiersExamples

 file-spec

  Specifies the image file to be patched or a command  procedure  that
  contains  both  the  name  of the image file to be patched and PATCH
  commands.

  If  the  file  specification  denotes  an  image  file,   the   file
  specification must contain the file name.  If you omit the remaining
  fields (device, directory, file type,  and  version  number),  PATCH
  uses  your default device and directory, assumes a file type of EXE,
  and uses the highest version of the image file.

  If the file specification denotes a command procedure, the file-spec
  parameter must be preceded by an at sign (@).  Only the file name is
  required.  If you omit the remaining fields (device, directory, file
  type,  and  version  number),  PATCH  uses  your  default device and
  directory, assumes a file type  of  COM,  and  locates  the  highest
  version of the command procedure.

  No wildcard characters are allowed in the file specification.

Additional information available:

/ABSOLUTE/JOURNAL/NEW_VERSION/OUTPUT/UPDATE
/VOLUME

 /ABSOLUTE

  Patches a file at absolute virtual addresses. The /ABSOLUTE function
  allows  a  user to patch any file (not just image files) at absolute
  virtual addresses relative to  the  beginning  of  the  file.   This
  feature  allows  replacement  of  existing data with new data of the
  same length.  If the data is smaller than that of the original data,
  PATCH  uses the appropriate fill character for the mode in use.  For
  example, if the current mode is instruction mode, a NOP is used  for
  fill;  if  it  is  data  (numeric or ASCII) mode, a NULL is used for
  fill.  Any PATCH operation that results in a data replacement longer
  than  the length of the original data generates an error message and
  terminates the command in progress; either the PATCH or  DCL  prompt
  is then displayed, whichever is appropriate.

  Also, note that there is no default patch area,  and  none  will  be
  created,  because  of the tendency to corrupt a file.  Patch area is
  meaningless in other than an image file.

  If you patch a file in absolute mode, remember that that  there  are
  no  symbols available to assist you in locating data locations.  You
  must exercise great care to ascertain that the correct locations are
  modified.

  Most PATCH commands will work in  their  normal  fashion.   However,
  only  REPLACE and DEPOSIT should be used for write operations; other
  commands are acceptable for read operations.  Commands that  attempt
  to  expand  the  file,  such  as ALIGN and INSERT, should be avoided
  because they will probably corrupt the file.  (These  commands  will
  be  trapped  by PATCH and an error message will be issued indicating
  that the replacement data must not exceed the length of the original
  data.)

  File attributes are propagated from the original input file  to  the
  output file.  These include ALQ, TYPE, MRS, RAT, RFM, and RAC.

 /JOURNAL[=file-spec]

 Indicates an alternate journal file specification.  By default, PATCH
  creates  a  journal  file with a file specification that consists of
  the current defaults.  Use the /JOURNAL qualifier when you  want  to
  specify  an alternate file specification.  If you omit fields in the
  file specification, PATCH supplies the following default values:

       Field                    Default Value

       device and directory     defaults of current process

       file name                name of input image file

       file type                JNL

       version                  1

  Subsequent PATCH sessions append information to  the  journal  file,
  rather than create a new version of this file.

  No wildcard characters are allowed in the file specification.

 /NEW_VERSION (default)
 /NONEW_VERSION

  Controls whether a new version of the patched file is created or the
  contents   of   the  existing  file  are  modified  in  place.   The
  /NEW_VERSION qualifier is used in  conjunction  with  the  /ABSOLUTE
  qualifier  to  control  whether a new version of the patched file is
  created or the contents of the existing file are modified in  place.
  /NEW_VERSION  is  the  default.   If /NONEW_VERSION is selected, the
  PATCH command UPDATE will act as a checkpoint  operation,  that  is,
  all  modifications  made  to  the  file are written back to the file
  instead of waiting until image exit.  If /ABSOLUTE is not  specified
  with  /NONEW_VERSION,  /NONEW_VERSION  is  ignored,  that  is, a new
  version of the file will be created.  /NONEW_VERSION will need to be
  used  when  patching  large data files when there is not enough disk
  space to create a new version of the patched file.

                                  NOTE

          If /NEW_VERSION  is  specified,  the  file  will  be
          overwritten.   No  attempt  on the part of the user,
          including  pressing  <CTRL/Y>,  will  prevent   this
          result.   Therefore,  you should have a back up copy
          of the file before making any attempt to patch it.

  PATCH will always issue an  informational  message  at  image  exit,
  indicating that the file is being overwritten.

 /OUTPUT[=file-spec]

 Indicates the output image file  specification.   By  default,  PATCH
  creates  an  output  file with a file specification that consists of
  the current defaults.  Use the /OUTPUT qualifier when  you  want  to
  specify an alternate file specification.

  If you omit fields in the file  specification,  PATCH  supplies  the
  following default values:

       Field                    Default Value

       device and directory     defaults of current process

       file name                name of input image file

       file type                EXE

       version                  one greater than the most recent
                                copy of the input image file

  The output image file is created  only  when  you  issue  the  PATCH
  command  UPDATE  at  the  end  of  the PATCH session.  You can issue
  multiple UPDATE commands in a  single  session.   The  first  UPDATE
  command  creates  the  output image file; subsequent UPDATE commands
  overwrite this file.

  No wildcard characters are allowed in the file specification.

 /UPDATE[=(eco-level[,...])]

  Requests that only the patches  associated with  the  specified  ECO
  levels  be  processed.   If you specify more than one ECO level, you
  must separate the ECO levels with commas and  enclose  the  list  in
  parentheses.

  When you specify the  /UPDATE  qualifier,  the  PATCH  command  file
  specification  denotes  either a command procedure that contains the
  patches to be processed or an image file to  which  certain  patches
  are  to  be  applied.  When the file specification denotes a command
  procedure, the /UPDATE qualifier must precede the file specification
  on  the  command line.  When the file specification denotes an image
  file,  the  /UPDATE  qualifier  can  precede  or  follow  the   file
  specification.  In either case, the file specification is required.

  If PATCH encounters an ECO level in a command  procedure  that  does
  not  match  the  ECO level specified on the /UPDATE qualifier, PATCH
  ignores the ensuing patch but displays a message.  Whenever you omit
  the  optional  ECO  levels, PATCH responds by processing all patches
  submitted.

 /VOLUME[=n]

  Requests that the output file be  placed  on  a  specified  relative
  volume  number of a multivolume set.  If you specify /VOLUME without
  a number, the number defaults to the relative volume number  of  the
  input image file.

  If the /VOLUME qualifier is not specified, the file is placed in  an
  arbitrary position within the multivolume set.

 1)    $ PATCH/ABSOLUTE IMAGE.EXE
       PATCH>EX/INS 604
       00000604:  BBSS    #07,R1,00000608
       PATCH>REPLACE/INS 604='BBSS #07,R1,0608'
       NEW>  'BBSS #07,R1,0608'
       NEW>  'CLRL R0'
       NEW>  EXIT
       old: 00000604:  BBSS    #07,R1,00000608
       %PATCH-E-DATTOOLNG, length of new data may not exceed length of
       old data
       PATCH>EX/INS 684
       00000684:  MOVB    #01,(R5)+
       PATCH>REPLACE/INS 684='MOVB #01,(R5)+'
       NEW>  'MOVB #02,(R5)+'
       NEW>  EXIT
       old: 00000684:  MOVB    #01,(R5)+
       new: 00000684:  MOVB    #02,(R5)+
       PATCH>EX/INS 687
       00000687:  MOVB    #00,(R5)+
       PATCH>DEPOSIT/INS 687
       NEW>  'CLRB (R5)+'
       NEW>  EXIT
       old: 00000687:  MOVB    #00,(R5)+
       new: 00000687:  CLRB    (R5)+
       PATCH>INSERT/INS 68D
       OLD>  'MOVB #10,(R5)+'
       NEW>  'MOVB #20,(R5)+'
       NEW>  EXIT
       old: 0000068D:  MOVB    #10,(R5)+
       %PATCH-E-DATTOOLNG, length of new data may not exceed length of
       old data
       PATCH>UPDATE
       %PATCH-I-WRTFIL, updating image file
       DISK$STARWORK01:[NASR.PATCH]IMAGE.EXE;2
       PATCH>EXIT

  An example of the  /ABSOLUTE  qualifier  with  /NEW_VERSION  as  the
  default.  Note the error messages returned when the command tries to
  expand the file.

 2)    $ PATCH/ABSOLUTE/NONEW_VERSION  LOGIN.COM
       PATCH>EX/ASCII 57
       00000057:  'MANA'
       PATCH>REPLACE/ASCII 57='MANA'
       NEW>  'mana'
       NEW>  'test'
       NEW>  exit
       old: 00000057:  'MANA'
       %PATCH-E-REPLACEERR, replacement value too large for location
       PATCH>replace/ascii 57='MANA'
       NEW>  'mana'
       NEW>  exit
       old: 00000057:  'MANA'
       new: 00000057:  'mana'
       PATCH>EX/ASCII 24
       00000024:  'F$MO'
       PATCH>INSERT/ASCII 24='F$MO'
       NEW>  'test'
       NEW>  exit
       %PATCH-E-INVCMD, invalid command
       PATCH>UPDATE
       %PATCH-I-OVERLAY, DISK$STARWORK01:[NASR.PATCH]LOGIN.COM;1 being
       overwritten
       PATCH>EX 68:75
       00000068:  4349544F
       0000006C:  58542E45
       00000070:  00010054
       00000074:  00100024
       PATCH>REPLACE 68
       OLD>  4349544F
       OLD>  58542E45
       OLD>  00010054
       OLD>  EXIT
       NEW>  6369746F
       NEW>  68642E65
       NEW>  00010074
       NEW>  EXIT
       old: 00000068:  4349544F
       old: 0000006C:  58542E45
       old: 00000070:  00010054
       new: 00000068:  6369746F
       new: 0000006C:  68642E65
       new: 00000070:  00010074
       PATCH>EX/ASCII 68
       00000068:  'otic'
       PATCH>UPDATE
       %PATCH-I-OVERLAY, DISK$STARWORK01:[NASR.PATCH]LOGIN.COM;1 being
       overwritten
       PATCH>EXIT
       %PATCH-I-OVERLAY, DISK$STARWORK01:[NASR.PATCH]LOGIN.COM;1 being
       overwritten
       $

  Example of a PATCH/ABSOLUTE/NONEW_VERSION command.  Note  the  error
  messages  that  are  returned  when  the command tries to expand the
  file, and when the commands UPDATE and EXIT are performed, that  is,
  (file)  "being overwritten."

 3)    $ PATCH AVERAGE /JOURNAL=TEST /OUTPUT=TEST

  This command invokes PATCH for an interactive PATCH session with the
  image  file  AVERAGE.EXE.   The  journal  file and output image file
  created by this session are  both  named  TEST  and  reside  in  the
  default  device  and directory.  The journal file has a file type of
  JNL, and the output image file has a file type of EXE.

 4)    $ PATCH /UPDATE=(100,102) @ORION
       $

  This PATCH command executes the command  procedure  ORION.COM.   The
  /UPDATE  qualifier  requests that only the patches identified by the
  ECO levels 100 and 102, contained in ORION.COM, be  processed.   The
  first  record  in  ORION.COM must specify the input image file.  The
  second DCL prompt ($) indicates that the patches  were  successfully
  applied.