CDEC$ IDENT string

 The IDENT directive lets you specify a string that can be used to
 identify an object module.  The compiler places the string in the
 identification field of an object module when it generates the
 module for each source program unit.  The string that you specify
 can consist of a group of up to 31 printable characters delimited
 by apostrophes.

 Only the first IDENT directive is effective -- the compiler ignores
 any additional IDENT directives in a program unit.

 CDEC$ OPTIONS

 The OPTIONS directive controls whether the DEC Fortran compiler
 naturally aligns fields in records and data items in common blocks
 for performance reasons, or whether the compiler packs those fields
 and data items together on arbitrary byte boundaries.  The OPTIONS
 directive takes the following form:

 CDEC$ OPTIONS /[NO]ALIGN[=p]
        .
        .
        .
 CDEC$ END OPTIONS

 p  Is a specifier with one of the following forms:

    [class =] rule    
    (class = rule,...) 
    ALL
    NONE

    class  Is one of the following keywords:

           COMMONS    (for common blocks)
           RECORDS    (for records)
           STRUCTURES (a synonym for RECORDS)

    rule   Is one of the following keywords:

           PACKED -   Packs fields in records or data 
                      items in common blocks on arbitrary 
                      byte boundaries.

           NATURAL -  Naturally aligns fields in records 
                      and data items in common blocks on 
                      up to 64-bit boundaries (inconsistent 
                      with the FORTRAN-77 standard).

                      If you specify NATURAL, the compiler will 
                      naturally align all data in a common 
                      block, including INTEGER*8, REAL*8, and 
                      all COMPLEX data.

           STANDARD - Naturally aligns data items in common 
                      blocks on up to 32-bit boundaries (con-
                      sistent with the FORTRAN-77 standard).

                      Note that this keyword only applies to 
                      common blocks; therefore, you can specify 
                      /ALIGN=COMMONS=STANDARD, but you cannot specify 
                      /ALIGN=STANDARD.

    ALL    Is the same as /ALIGN, /ALIGN=NATURAL, and 
           /ALIGN=(RECORDS=NATURAL,COMMONS=NATURAL).

    NONE   Is the same as /NOALIGN, /ALIGN=PACKED, and
           /ALIGN=(RECORDS=PACKED,COMMONS=PACKED)

 CDEC$ OPTIONS (and accompanying CDEC$ END OPTIONS) directives must
 come after OPTIONS, SUBROUTINE, FUNCTION, and BLOCK DATA statements
 (if any) in the program unit, and before statement functions or the
 executable part of the program unit.

 For performance reasons, DEC Fortran always aligns local data items
 on natural boundaries.  However, EQUIVALENCE, COMMON, RECORD, and
 STRUCTURE data declaration statements can force misaligned data.
 You can use the CDEC$ OPTIONS directive to control the alignment of
 fields associated with COMMON and RECORD statements.  By default,
 you receive compiler messages when misaligned data is encountered.

 To request packed, unaligned data in a record structure, specify
 /ALIGN=RECORDS=PACKED, or consider placing source data declarations
 for the record so that the data is naturally aligned.

                                NOTE

         Misaligned data significantly increases the time it
         takes  to  execute  a  program.   As  the number of
         misaligned fields encountered  increases,  so  does
         the  time  needed  to  complete  program execution.
         Specifying  CDEC$  OPTIONS/ALIGN  (or  the   /ALIGN
         compiler option) minimizes misaligned data.


 To request aligned, data in common blocks, specify
 /ALIGN=COMMONS=STANDARD (for data items up to 32 bits in length) or
 /ALIGN=COMMONS=NATURAL (for data items up to 64 bits in length), or
 place source data declarations within the common block in
 descending size order, so that each data field is naturally
 aligned.

 The CDEC$ OPTIONS directive supersedes the -align "keyword"
 compiler option.

 CDEC$ OPTIONS directives must be balanced and can be nested up to
 100 levels, for example:

    CDEC$ OPTIONS /ALIGN=PACKED         ! Group A
       declarations
    CDEC$ OPTIONS /ALIGN=RECO=NATU         ! Group B
       more declarations
    CDEC$ END OPTIONS                      ! End of Group B
       still more declarations
    CDEC$ END OPTIONS                   ! End of Group A

 Note that common blocks within Group B will be PACKED.  The CDEC$
 OPTION specification for Group B only applies to RECORDS, so
 COMMONS retains the previous setting (in this case, from the Group
 A specification).

 For more information on alignment and data sizes, see your user
 manual.

 CDEC$ PSECT /common-name/ attr [,attr,...]

 The PSECT directive lets you modify several attributes of a common
 block.

 Specify the name of a common block, preceded and followed by a
 slash, and one of the following attributes:
    LCL (VMS only)         Local scope.
    GBL (VMS only)         Global scope.
    [NO]WRT (VMS only)     Writability or no-writability.
    [NO]SHR (VMS only)     Shareability or no-shareability.
    ALIGN=val              Alignment for the common block.
                             The "val" must be a constant 
                                            (0 through 9).

 CDEC$ TITLE string
 CDEC$ SUBTITLE string

 The TITLE directive lets you specify a string and place it in the
 title field of a listing header.  Similarly, SUBTITLE lets you
 place a specified string in the subtitle field of a listing header.

 The string that you specify can consist of up to 31 printable
 characters and must be delimited by apostrophes.

 In addition to the compiler-directive syntax rules, the TITLE and
 SUBTITLE directives have the following specific rules:

  -  To enable TITLE and SUBTITLE directives, you must specify the
     -V compiler option.

  -  When TITLE or SUBTITLE appears on a page of a listing file, the
     specified string appears in the listing header of the following
     page.

  -  If two or more of either directive appear on a page, the last
     directive is the one in effect for the following page.

  -  If either directive does not specify a string, no change occurs
     in the listing file header.