VMS Help MACRO, VAX MACRO Assembler, Directives, .ASCIx  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    ASCII character storage directives

    VAX MACRO has four ASCII character storage directives:

    Directive        Function
    ASCIC            Counted ASCII string storage
    ASCID            String-descriptor ASCII string storage
    ASCII            ASCII string storage
    ASCIZ            Zero-terminated ASCII string storage

    Each directive is followed by a string of characters  enclosed  in
    a pair  of  matching  delimiters.   The delimiters can be any
    printable character  except  the  space  or  tab  character,  equal
    sign  (=), semicolon (;), or left angle bracket (<).  The character
    that you use as the delimiter cannot appear in the string  itself.
    Although  you can  use  alphanumeric  characters as delimiters, use
    nonalphanumeric characters to avoid confusion.

    Any character  except  the  null,  carriage  return,  and  form
    feed characters  can  appear  within  the  string.  The assembler
    does not convert lowercase alphabetic characters to uppercase.

    ASCII character storage directives convert the  characters  to
    their 8-bit ASCII and store them one character to a byte.

    Any character, including the null, carriage  return,  and  form
    feed characters,  can  be  represented  by an expression enclosed
    in angle brackets outside of the delimiters.  You must define the
    ASCII values of  null,  carriage  return,  and  form feed with a
    direct assignment statement.  The ASCII character storage
    directives  store  the  8-bit binary value specified by the
    expression.

    ASCII strings can be continued over several lines.  Use the hyphen
    as the  line  continuation character and delimit the string on each
    line at both ends.  Note that you can use a different pair  of
    delimiters for each line.

1 - .ASCIC

    Performs the same function as .ASCII, except that  .ASCIC  inserts
    a count  byte  before  the  string  data.   The count byte contains
    the length of the string in bytes.  The length given includes  any
    bytes of  nonprintable characters outside the delimited string but
    excludes the count byte.

    .ASCIC string

    string

    A delimited ASCII string.

2 - .ASCID

    Performs the same function as ASCII, except  that  .ASCID  inserts
    a string descriptor before the string data.

    .ASCID string

    string

    A delimited ASCII string.

    The string descriptor has the following format:

        31                                 0
        ____________________________________
        |  information   |   length        |
        +----------------+-----------------+
        |              pointer             |
        +----------------------------------+

    length

    The length of the string (two bytes).

    information

    Descriptor information (two bytes) is always set to 010E.

    pointer

    Position independent pointer to the string (four bytes).

    String descriptors are used in calling procedures.

3 - .ASCII

    Stores the ASCII value of each character in the ASCII string  or
    the value of each byte expression in the next available byte.

    .ASCII string

    string

    A delimited ASCII string.

4 - .ASCIZ

    Performs the same function as .ASCII, except that  .ASCIZ  appends
    a null  byte as the final character of the string.  When a list or
    text string is created with an .ASCIZ directive, you need only
    perform  a search  for  the null character in the last byte to
    determine the end of the string.

    .ASCIZ string

    string

    A delimited ASCII string.