Example

 $ MESSAGE = F$MESSAGE(%X1C)
 $ SHOW SYMBOL MESSAGE
   MESSAGE = "%SYSTEM-F-EXQUOTA, exceeded quota"
 $ STRING_LENGTH = F$LENGTH(MESSAGE)
 $ SHOW SYMBOL STRING_LENGTH
   STRING_LENGTH = 33   Hex = 00000021  Octal = 000041

     The first assignment statement uses the F$MESSAGE function
     to return the message that corresponds to the hexadecimal
     value 1C. The message is returned as a character string and
     is assigned to the symbol MESSAGE.

     The F$LENGTH function is then used to return the length of
     the character string assigned to the symbol MESSAGE. You
     do not need to use quotation marks (" ")  when you use the
     symbol MESSAGE as an argument for the F$LENGTH function.
     (Quotation marks are not used around symbols in character
     string expressions.)

     The F$LENGTH function returns the length of the character
     string and assigns it to the symbol STRING_LENGTH. At the end
     of the example, the symbol STRING_LENGTH has a value equal
     to the number of characters in the value of the symbol named
     MESSAGE, that is, 33.