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9.0;for, revision 9.0, 85/03/28
FOR -- Execute a FOR statement.
usage:
      FOR var_name := int_expr [TO int_expr] [BY int_expr] command... ENDFOR
      FOR var_name IN string_expr [BY {CHAR|WORD|LINE}]    command... ENDFOR


FORMAT

  FOR var_name := int_expr [TO int_expr] [BY int_expr] command... ENDFOR

  FOR var_name IN string_expr [BY {CHAR|WORD|LINE}]    command... ENDFOR


  FOR  allows you to build a control structure that executes commands repeatedly
  as long as the result of a Boolean test is TRUE.   The  FOR  command  has  two
  formats:  one  for  assigning  and  testing  integer  expressions, and one for
  assigning and testing string expressions.

  In the integer form, the (optional) TO and BY clauses permit  you  to  specify
  ranges  and  increment  values,  respectively.  For example, you might want to
  loop 5 times by saying

    FOR a := 0 TO 10 BY 2

  If you do not specify "BY int_expr", the default increment is 1.   If  you  do
  not  specify  "TO  int_expr", you will probably want to increment the variable
  manually inside the body of the loop.  You should also put  a  test  condition
  inside the loop (and probably use an EXIT to get out) or else you risk looping
  forever.

  In the string form, the (optional) BY clause allows you to control the  string
  assignment  operation.    If you specify "BY WORD" (the default), each word (a
  sequence of non-blank characters) in 'string_expr' is assigned  to  'var_name'
  one  at  a  time until 'string_expr' is exhausted.  You may also assign string
  values a character at a time, or a line at a time, by using the "BY CHAR"  and
  "BY LINE" clauses, respectively.


ARGUMENTS

  var_name
  (required)         Specify the name of the Shell variable whose value is to be
                     assigned and tested.

  int_expr
  (required)         Specify any valid expression that returns an integer value.

  string_expr
  (required)         Specify any valid expression that returns a string value.

  command...
  (required)         Specify the command to be executed as long as the FOR  test
                     returns TRUE.  This may be a Shell command, a Shell script,
                     a variable assignment, or any other valid Shell  operation.
                     Multiple   commands   are  permitted;  separate  them  with
                     semicolons or NEWLINE characters.


EXAMPLES

     1. The following example demonstrates the advantages  of  a  FOR  loop
        over  a  WHILE loop in one instance.  Assume these line appear in a
        Shell script.

               #
               # A loop using WHILE.
               #
               eon
               a := 0
               while ((^a <= 10)) do
                   args ^a
                   a := ^a + 2
               enddo
               #
               # The same loop using FOR.
               #
               FOR a := 0 TO 10 BY 2
                   args ^a
               ENDFOR
               #
               # End of script.

     2. This example assigns three names to a variable.

               #
               # Script FILE_NAME
               #
               eon
               FOR file IN "foo bar zap" BY word
                   args ^file
               ENDFOR
               #
               # End of script.

        Execution produces:

               $ file_name
               foo
               bar
               zap
               $