comm Command
  
  
  Purpose
  
  Selects or rejects lines common to two sorted files.
  
   Syntax
  
  comm [  -1  -2  -3 ] File1 File2
  
  Description
  
  Note:	If you specify - (minus) for one of the file names, the
  comm command reads standard input.
  
  The comm command reads the File1 and File2 parameters and writes,
  by  default,  a  three-column  output to standard  output.    The
  columns consist of:
  
  *	Lines that are only in File1
  
  *	Lines that are only in File2
  
  *	Lines that are in both File1 and File2.
  
   Both File1 and File2 should be sorted according to the collating
  sequence specified by the current National Language evironment.
  
  Flags
  
  -1	Suppresses the display of the first column (lines in File1).
  
  -2	Suppresses the display of the second column (lines in File2).
  
  -3	Suppresses the display of the third column (lines common to
  File1 and File2).
  
  Exit Status
  
  This command returns the following exit values:
  
  0	All input files were output successfully.
  
  >0	An error occurred.
  
  Examples
  
  1.	To display the lines unique to each file and common to both,
  enter:
  
  comm  things.to.do  things.done
  
  If the files things.to.do and things.done contain the following
  lists:
  
  things.to.do
  
  buy soap
  groceries
  luncheon
  meeting at 3
  system update
  tech. review
  
  things.done
  
  2nd revision
  interview
  luncheon
  system update
  tech. review
  weekly report
  
  then the comm command displays:
  
         2nd revision
  buy soap
  groceries
         interview
                 luncheon
  meeting at 3
                 system update
                 tech. review
         weekly report
  
  The first column contains the lines found only in things.to.do.
  The second column, indented with a tab character, lists the lines
  found only in things.done.  The third column, indented with two
  tabs, lists the lines common to both.
  
  2.	To display the lines that appear in only one file, enter:
  
  comm  -23  things.to.do things.done
  
  This suppresses the second and third columns of the comm command
  listing.  If  the  files  are  the same as in Example 1, then the
  following is displayed:
  
  buy soap
  groceries
  meeting at 3
  
  Implementation Specifics
  
  This command is part of Base Operating System (BOS) Runtime.
  
  Files
  
  /usr/bin/comm	Path to the comm command.
  
  Related Information
  
   Understanding Locale in AIX Version 3.2 System Management Guide:
  Operating System and Devices.
  
  The  cmp command,  diff command,  sdiff command,  sort command, 
  uniq command.
  
  The  environment file.