/CHANGE_BAR[=([change-char][,[NO]NUMBER])]
Marks differences using the specified character. The /CHANGE_BAR 
qualifier displays output that depends on where the qualifier is 
placed. The following examples describe the result of /CHANGE_BAR 
qualifier placement.
The following placement displays the latest version of 
input.file with the pound sign (#) preceding any lines that 
differ from the preceding version of input.file:
  
    
       
      
$ DIFFERENCES input.file/CHANGE_BAR=#
 
 | 
The following placement displays input.file;2 with the pound 
sign (#) preceding any lines that differ from input.file;1:
  
    
       
      
$ DIFFERENCES input.file;1  input.file;2 /CHANGE_BAR=#
 
 | 
The following placement displays input.file;1 with the pound 
sign (#) preceding any lines that differ from input.file;2:
  
    
       
      
$ DIFFERENCES input.file;1/CHANGE_BAR=#  input.file;2
 
 | 
The following placement displays input.file;1 with the percent 
sign (%) preceding any lines that differ from input.file;2, 
and also displays input.file;2 with the pound sign (#) 
preceding any lines that differ from input.file;1:
  
    
       
      
$ DIFFERENCES input.file;1/CHANGE_BAR=% input.file;2/CHANGE_BAR=#
 
 | 
  - If you do not specify a change bar character, the default is an 
  exclamation point (!) for ASCII output.
  
 - If you specify hexadecimal or octal output (see the description of 
  the /MODE qualifier), the change bar character is ignored and 
  differences are marked by a "***CHANGE***" string in the 
  record header. The keyword NONUMBER suppresses line numbers in the 
  listing.
  
 - If neither the NUMBER nor the NONUMBER keyword is specified, the 
  default is controlled by the /[NO]NUMBER command qualifier.
  
 - If you specify only one option, you can omit the parentheses.
  
 - If you use an exclamation point (!) as the specified character, you 
  must enclose it in quotation marks (" "); for example, 
  /CHANGE_BAR=("!",NUMBER).
 
/COMMENT_DELIMITER[=(character[,...])]
Ignores characters on a line to the right of (and including) a 
specified comment character.
If you specify just one character, you can omit the parentheses. 
Lowercase characters are automatically converted to uppercase unless 
they are enclosed in quotation marks. Nonalphanumeric characters (such 
as ! and ,) must be enclosed in quotation marks. Multicharacter comment 
characters are not allowed. You can specify up to 32 comment characters 
by typing the character itself or one of the following keywords. 
(Keywords can be abbreviated provided that the resultant keyword is not 
ambiguous and has at least 2 characters; single letters are treated as 
delimiters.)
  
    | Keyword  | 
    Character  | 
  
  
    | 
      COLON
     | 
    
      Colon (:)
     | 
  
  
    | 
      COMMA
     | 
    
      Comma (,)
     | 
  
  
    | 
      EXCLAMATION
     | 
    
      Exclamation point (!)
     | 
  
  
    | 
      FORM_FEED
     | 
    
      Form feed
     | 
  
  
    | 
      LEFT
     | 
    
      Left bracket ([)
     | 
  
  
    | 
      RIGHT
     | 
    
      Right bracket (])
     | 
  
  
    | 
      SEMI_COLON
     | 
    
      Semicolon (;)
     | 
  
  
    | 
      SLASH
     | 
    
      Slash (/)
     | 
  
  
    | 
      SPACE
     | 
    
      Space
     | 
  
  
    | 
      TAB
     | 
    
      Tab
     | 
  
If you specify the /COMMENT_DELIMITER qualifier, the /IGNORE=COMMENTS 
qualifier is implicitly also included.
If both the uppercase and lowercase forms of a letter are to be used as 
comment characters, the letter must be specified twice, once in 
uppercase and once in lowercase. If you do not include either a comment 
character or a keyword with the /COMMENT_DELIMITER qualifier, the 
DIFFERENCES command assumes a default comment character based on the 
file type. For some file types (.COB and .FOR), the default comment 
characters are considered valid delimiters only if they appear in the 
first column of a line.
The following characters are the default comment delimiters for files 
with the specified file types:
  
    | File Type  | 
    Default Comment Character  | 
  
  
    | 
      .B2S, .B32, .BAS, .BLI
     | 
    
      !
     | 
  
  
    | 
      .CBL, .CMD
     | 
    
      ! and ;
     | 
  
  
    | 
      .COB
     | 
    
      * or / in the first column
     | 
  
  
    | 
      .COM, .COR
     | 
    
      !
     | 
  
  
    | 
      .FOR
     | 
    
      ! anywhere and C, D, c, d in the first column
     | 
  
  
    | 
      .HLP
     | 
    
      !
     | 
  
  
    | 
      .MAC, .MAR
     | 
    
      ;
     | 
  
  
    | 
      .R32, .REQ
     | 
    
      !
     | 
  
/EXACT
Use with the /PAGE=SAVE and /SEARCH qualifiers to specify a search 
string that must match the search string exactly and must be enclosed 
with quotation marks (" ").
If you specify the /EXACT qualifier without the /SEARCH qualifier, 
exact search mode is enabled when you set the search string with the 
Find (E1) key.
/HIGHLIGHT[=keyword]
Use with the /PAGE=SAVE and /SEARCH qualifiers to specify the type of 
highlighting you want when a search string is found. When a string is 
found, the entire line is highlighted. You can use the following 
keywords: BOLD, BLINK, REVERSE, and UNDERLINE. BOLD is the default 
highlighting.
/IGNORE=(keyword[,...])
Inhibits the comparison of the specified characters, strings, or 
records; also controls whether the comparison records are output to the 
listing file as edited records or exactly as they appeared in the input 
file. If you specify only one keyword, you can omit the parentheses. 
The keyword parameter refers to either a character or a keyword. The 
first set of keywords determines what, if anything, is ignored during 
file comparison; the second set of keywords determines whether or not 
ignored characters are included in the output. The following keywords 
are valid options for the /IGNORE qualifier:
  
    | Keyword  | 
    Item Ignored  | 
  
  
    | 
      BLANK_LINES
     | 
    
      Blank lines between data lines.
     | 
  
  
    | 
      CASE
     | 
    
      Case of the text being compared.
     | 
  
  
    | 
      COMMENTS
     | 
    
      Data following a comment character. (Use the /COMMENT_DELIMITER 
      qualifier to designate one or more nondefault comment delimiters.)
     | 
  
  
    | 
      FORM_FEEDS
     | 
    
      Form feed character.
     | 
  
  
    | 
      HEADER[=n]
     | 
    
      Defines
      n records of the file as header records, beginning with a 
      record whose first character is a form feed. The first record is not 
      ignored if the only character it contains is a form feed. (
      n indicates the header size and defaults to 2. A record 
      containing only a single form feed is not counted in
      n.)
     | 
  
  
    | 
      SPACING
     | 
    
      Extra spaces or tabs within data lines.
     | 
  
  
    | 
      TRAILING_SPACES
     | 
    
      Space and tab characters at the end of a data line.
     | 
  
  
    | 
      WHITE_SPACE
     | 
    
      All spaces and tab characters.
     | 
  
  
    | Keyword  | 
    Status of Ignored Items in Output  | 
  
  
    | 
      EDITED
     | 
    
      Omits ignored characters from the output records.
     | 
  
  
    | 
      EXACT
     | 
    
      Includes ignored characters in the output records.
     | 
  
  
    | 
      PRETTY
     | 
    
      Formats output records.
     | 
  
Each data line is checked for COMMENTS, FORM_FEEDS, HEADER, and SPACING 
before it is tested for TRAILING_SPACES and then BLANK_LINES. 
Therefore, if you direct the DIFFERENCES command to ignore COMMENTS, 
TRAILING_SPACES, and BLANK_LINES, it ignores a record that contains 
several spaces or blank lines followed by a comment.
By default, the DIFFERENCES command compares every character in each 
file and reports all differences. Also, by default, the DIFFERENCES 
command lists records in the output file with all ignored characters 
deleted.
If you specify the /PARALLEL qualifier, output records are always 
formatted. The following table shows the corresponding output for the 
various characters that are being translated:
  
    | Character  | 
    Formatted Output  | 
  
  
    | 
      Tab (Ctrl/I)
     | 
    
      1--8 spaces
     | 
  
  
    | 
      Return (Ctrl/M)
     | 
    
      <CR>
     | 
  
  
    | 
      Line feed (Ctrl/J)
     | 
    
      <LF>
     | 
  
  
    | 
      Vertical tab (Ctrl/K)
     | 
    
      <VT>
     | 
  
  
    | 
      Form feed (Ctrl/L)
     | 
    
      <FF>
     | 
  
  
    | 
      Other nonprinting characters
     | 
    
      . (period)
     | 
  
/MATCH=size
Specifies the number of records that should indicate matching data 
after a difference is found. By default, after the DIFFERENCES command 
finds unmatched records, it assumes that the files once again match 
after it finds three sequential records that match. Use the /MATCH 
qualifier to override the default match size of 3.
You can increase the /MATCH qualifier value if you feel that the 
DIFFERENCES command is incorrectly matching sections of the master and 
revision input files after it has detected a difference.
/MAXIMUM_DIFFERENCES=n
Terminates the DIFFERENCES command after the specified number of 
unmatched records (specified with the n parameter) is found.
The number of unmatched records is determined by finding the maximum 
number of difference records for each difference section and adding 
them together.
If the DIFFERENCES command reaches the maximum number of differences 
that you specify, it will output only those records that were detected 
before the maximum was reached. Also, it will output, at most, one 
listing format and return a warning message.
By default, there is no maximum number of differences. All records in 
the specified input files are compared.
/MERGED[=n]
Specifies that the output file contain a merged list of differences 
with the specified number of matched records listed after each group of 
unmatched records. The value of the parameter n must be less 
than or equal to the number specified in the /MATCH qualifier. By 
default, the DIFFERENCES command produces a merged listing with one 
matched record listed after each set of unmatched records (that is, 
/MERGED=1). If the /MERGED, /SEPARATED, or /PARALLEL qualifier is not 
specified, the resulting output is merged, with one matched record 
following each unmatched record.
Use the /MERGED qualifier to override the default value of the 
parameter n, or to include a merged listing with other types 
of output.
/MODE=(radix[,...])
Specifies the format of the output. You can request that the output be 
formatted in one or more radix modes by specifying the following 
keywords, which may be abbreviated: ASCII (default), HEXADECIMAL, or 
OCTAL. If you specify only one radix, you can omit the parentheses.
By default, the DIFFERENCES command writes the output file in ASCII. If 
you specify more than one radix, the output listing contains the file 
comparison in each specified radix. When you specify two or more radix 
modes, separate them with commas.
If you specify the /PARALLEL or the /SLP qualifier, the /MODE qualifier 
is ignored for that listing form.
/NUMBER (default)
/NONUMBER
Includes line numbers in the listing of DIFFERENCES.
/OUTPUT[=filespec]
Specifies an output file to receive the list of differences. By 
default, the output is written to the current SYS$OUTPUT device. If the 
filespec parameter is not specified, the output is directed to 
the first input file with a file type .DIF. The asterisk (*) and the 
percent sign (%) wildcard characters are not allowed.
When you specify the /OUTPUT qualifier, you can control the defaults 
applied to the output file specification as described in the 
OpenVMS User's Manual. The default output file type is .DIF.
/PAGE[=keyword]
/NOPAGE (default)
Controls the display of difference information on the screen.
You can use the following keywords with the /PAGE qualifier:
  
    | 
      CLEAR_SCREEN
     | 
    
      Clears the screen before each page is displayed.
     | 
  
  
    | 
      SCROLL
     | 
    
      Displays information one line at a time.
     | 
  
  
    | 
      SAVE[=
      n]
     | 
    
      Enables screen navigation of information, where
      n is the number of pages to store.
     | 
  
The /PAGE=SAVE qualifier allows you to navigate through screens of 
information. The /PAGE=SAVE qualifier stores up to 5 screens of up to 
255 columns of information. When you use the /PAGE=SAVE qualifier, you 
can use the following keys to navigate through the information:
  
    | Key Sequence  | 
    Description  | 
  
  
    | 
      Up arrow key, Ctrl/B
     | 
    
      Scroll up one line.
     | 
  
  
    | 
      Down arrow key
     | 
    
      Scroll down one line.
     | 
  
  
    | 
      Left arrow key
     | 
    
      Scroll left one column.
     | 
  
  
    | 
      Right arrow key
     | 
    
      Scroll right one column.
     | 
  
  
    | 
      Find (E1)
     | 
    
      Specify a string to find when the information is displayed.
     | 
  
  
    | 
      Insert Here (E2)
     | 
    
      Scroll right one half screen.
     | 
  
  
    | 
      Remove (E3)
     | 
    
      Scroll left one half screen.
     | 
  
  
    | 
      Select (E4)
     | 
    
      Toggle 80/132 column mode.
     | 
  
  
    | 
      Prev Screen (E5)
     | 
    
      Get the previous page of information.
     | 
  
  
    | 
      Next Screen (E6), Return, Enter, Space
     | 
    
      Get the next page of information.
     | 
  
  
    | 
      F10, Ctrl/Z
     | 
    
      Exit. (Some utilities define these differently.)
     | 
  
  
    | 
      Help (F15)
     | 
    
      Display utility help text.
     | 
  
  
    | 
      Do (F16)
     | 
    
      Toggle the display to oldest/newest page.
     | 
  
  
    | 
      Ctrl/W
     | 
    
      Refresh the display.
     | 
  
The /PAGE qualifier is not compatible with the /OUTPUT qualifier.
/PARALLEL[=n]
Lists the records with differences side by side. The value of the 
parameter n specifies the number of matched records to merge 
after each unmatched record; it must be a non-negative decimal number 
less than or equal to the number specified in the /MATCH qualifier.
By default, the DIFFERENCES command does not list records after each 
list of unmatched records. Also by default, the DIFFERENCES command 
creates only a list of merged differences.
/SEARCH="string"
Use with the /PAGE=SAVE qualifier to specify a string that you want to 
find in the information being displayed. Quotation marks are required 
for the /SEARCH qualifier, if you include spaces in the text string.
You can also dynamically change the search string by pressing the Find 
key (E1) while the information is being displayed. Quotation marks are 
not required for a dynamic search.
/SEPARATED[=MASTER, REVISION]
Lists sequentially only the records from the specified file that 
contain differences. Use the MASTER keyword to list the differences in 
the first input file specified; use the REVISION keyword to list the 
differences in the second input file specified.
By default, the DIFFERENCES command creates only a merged list of 
differences.
/SLP
Requests that the DIFFERENCES command produce an output file suitable 
for input to the SLP editor. If you use the /SLP qualifier, you cannot 
specify any of the following output file qualifiers: /MERGED, 
/PARALLEL, /SEPARATED, or /CHANGE_BAR.
Use the output file produced by the SLP qualifier as input to SLP to 
update the master input file, that is, to make the master input file 
match the revision input file.
When you specify the /SLP qualifier and you do not specify the /OUTPUT 
qualifier, the DIFFERENCES command writes the output file to a file 
with the same file name as the master input file with the file type DIF.
/WIDTH=n
Specifies the width of the lines in the output file. The default is 132 
characters. If output is written to the terminal, the /WIDTH qualifier 
is ignored and the terminal line width is used.
Use the SET TERMINAL command to change the terminal line width.
/WINDOW=size
Searches the number of records specified by the size 
parameter, before a record is declared as unmatched. By default, the 
DIFFERENCES command searches to the ends of both input files before 
listing a record as unmatched.
The window size is the minimum size of a differences section that will 
cause the DIFFERENCES command to lose synchronization between the two 
input files.
/WRAP
/NOWRAP (default)
Use with the /PAGE=SAVE qualifier to limit the number of columns to the 
width of the screen and to wrap lines that extend beyond the width of 
the screen to the next line.
The /NOWRAP qualifier extends lines beyond the width of the screen and 
can be seen when you use the scrolling (left and right) features 
provided by the /PAGE=SAVE qualifier.