Defines a symbolic name for a character string or integer value.

  Format:

    symbol-name =[=] expression

  symbol-name[bit-position,size] =[=] replacement-expression

Additional information available:

ParametersExamples

 symbol-name

  Defines a 1- through 255-character alphanumeric string name for  the
  symbol.   The  symbol  name  must begin with an alphabetic character
  (uppercase and lowercase characters are equivalent), an  underscore,
  or  a  dollar sign.  After the first character, the name can contain
  any alphanumeric characters from  the  DEC  Multinational  Character
  Set, underscores, or dollar signs.

  If you specify a single equal sign (=) in the assignment  statement,
  the  symbol name is placed in the local symbol table for the current
  command level.

  If you specify double equal signs (==) in the assignment  statement,
  the symbol name is placed in the global symbol table.

 expression

  Specifies  the  value  on  the  right-hand  side  of  an  assignment
  statement.   An  expression can consist of a character string value,
  an  integer  value,  a  symbol  name,  a  lexical  function,  or   a
  combination  of these entities.  The components of an expression are
  evaluated, and the result is assigned to a symbol.

  All literal character strings must be enclosed in  quotation  marks.
  If  you  specify  an  expression  containing  a  symbol, the command
  interpreter uses the symbol's value in evaluating the expression.

  The result of expression evaluation is either a character string  or
  an  integer  value.   The data type of a symbol is determined by the
  data type of the expression.   If  the  expression  evaluates  to  a
  string,  the  symbol  is assigned a string value.  If the expression
  evaluates to an integer, the symbol is assigned an integer value.

  DCL uses a buffer that is 1024 bytes  long  to  hold  an  assignment
  statement, and to evaluate the expression.  The length of the symbol
  name, the  expression,  and  the  expression's  calculations  cannot
  exceed 1024 bytes.

 [bit-position,size]

  Specifies that a binary overlay is to be  inserted  in  the  current
  32-bit  value  of  a symbol-name.  This type of assignment statement
  evaluates the current value of  the  symbol-name  and  replaces  the
  specified    number    of    bits    with    the   result   of   the
  replacement-expression.

  The bit-position is the location relative to  bit  0  at  which  the
  overlay  is  to  occur.  If the symbol that you are overlaying is an
  integer, then the bit position must be less than 32.  Also, the  sum
  of the bit position and the size must be less than or equal to 32.

  If the symbol you are overlaying is a string, then the bit  position
  must be less than 6152.  Because each character is represented using
  8 bits, you can begin an overlay at any character through the 768th.
  (The  768th  character  starts in bit position 6144.) The sum of the
  bit position and the size must be less than or equal to 6152.

  The size is the number of bits to be overlaid.   If  you  specify  a
  size that is greater than 32, then DCL reduces the size to 32.

  The square brackets are required notation;  no  spaces  are  allowed
  between  the  symbol  name and the left bracket.  Specify values for
  bit-position and size as integer expressions.

 replacement-expression

  Specifies the value that is used  to  overlay  the  symbol  you  are
  modifying.    Specify   the  replacement-expression  as  an  integer
  expression.

  If   the   symbol   you   are   modifying   is   an   integer,   the
  replacement-expression  defines  a  bit pattern which is overlaid on
  the value assigned to the symbol.  If the symbol you  are  modifying
  is  a  character  string,  the  result of the replacement-expression
  defines a bit pattern which is overlaid on the specified bits of the
  character string.  If the symbol you are modifying is undefined, the
  result of the replacement-expression is overlaid on a null string.

  1.   $ LIST == "DIRECTORY"
       $ TIME == "SHOW TIME"
       $ QP == "SHOW QUEUE/DEVICE"
       $ SS == "SHOW SYMBOL"

  The file SYNONYM.COM contains the assignment statements shown; these
  are  user-defined  synonyms  for  commands.   Execute  this  command
  procedure as follows:

       $ @SYNONYM

  After the command procedure creates the global  symbol  definitions,
  you  can  use  these  synonyms  (LIST,  TIME,  QP,  and  SS)  at the
  interactive command level.  Note that the  assignments  are  global;
  otherwise,  the  symbol names would have been deleted after the file
  SYNONYM.COM completed execution.

  2. $ COUNT = 0
       $ LOOP:
       $      COUNT = COUNT + 1
               .
               .
               .

       $      IF COUNT .LT.5 THEN GOTO LOOP

  The symbol COUNT is initially assigned a numeric value of 0; a  loop
  is  established  to  increment the value of COUNT by 1 each time the
  loop is entered.  Note that when the symbol name  COUNT  appears  on
  the  right-hand  side  of  an  arithmetic  assignment statement, the
  command interpreter automatically substitutes its current value.

  The IF command tests the value of COUNT; if it is less than  5,  the
  procedure  branches to the label LOOP and the statements between the
  label LOOP through the IF command  are  executed  again.   When  the
  value  of the symbol count reaches 5, the loop is not executed again
  and the command following the IF command is executed.

  3. $ A = 25
       $ CODE = 4 + F$INTEGER("6") - A
       $ SHOW SYMBOL CODE
         CODE = -15   HEX = FFFFFFF1   Octal = 1777761

  This  example  contains  two  assignment  statements.    The   first
  statement  assigns  the  value  25  to  the  symbol  A.   The second
  assignment statement evaluates an expression containing  an  integer
  (4),  a  lexical  function  (F$INTEGER("6")), and the symbol A.  The
  result of the expression, -15, is assigned to the symbol CODE.