CCCCDDDDEEEECCCCLLLL((((1111))))                 SSSSYYYYSSSSTTTTEEEEMMMM VVVV////66668888 3333....1111                 CCCCDDDDEEEECCCCLLLL((((1111))))



     NNNNAAAAMMMMEEEE
          cdecl - Compose C declarations

     SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
          ccccddddeeeeccccllll

     DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
          _C_d_e_c_l is a program for encoding and decoding C type-
          declarations.  It reads standard input for statements in the
          language described below.  The results are written on
          standard output.

          _C_d_e_c_l'_s scope is intentionally small.  It doesn't help you
          figure out storage classes or initializations.

     CCCCOOOOMMMMMMMMAAAANNNNDDDD LLLLAAAANNNNGGGGUUUUAAAAGGGGEEEE
          There are four statements in the language.  The "declare"
          statement composes a C type-declaration from a verbose
          description.  The "cast" statement composes a C type-cast as
          might appear in an expression.  The "explain" statement
          decodes a C type-declaration, producing a verbose
          description.  The "help" statement describes the others.

          The following grammar describes the language.  In the
          grammar, words in "<>" are non-terminals, bare lower-case
          words are terminals that stand for themselves.  Bare upper-
          case words are other lexical tokens: NOTHING means the empty
          string; NAME means a C identifier; NUMBER means a string of
          decimal digits; and NL means the new-line character.

          <program>    ::= NOTHING
                         | <program> <stat> NL
          <stat>       ::= NOTHING
                         | declare NAME as <decl>
                         | cast NAME into <decl>
                         | explain <cdecl>
                         | help
          <decl>       ::= array of <decl>
                         | array NUMBER of <decl>
                         | function returning <decl>
                         | function ( NAME ) returning <decl>
                         | pointer to <decl>
                         | <type>
          <cdecl>      ::= <cdecl1>
                         | * <cdecl>
          <cdecl1>     ::= <cdecl1> ( )
                         | <cdecl1> [ ]
                         | <cdecl1> [ NUMBER ]
                         | ( <cdecl> )
                         | NAME
          <type>       ::= <typename> | <modlist>
                         | <modlist> <typename>



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                         | struct NAME | union NAME | enum NAME
          <typename>   ::= int | char | double | float
          <modlist>    ::= <modifier> | <modlist> <modifier>
          <modifier>   ::= short | long | unsigned

     EEEEXXXXAAAAMMMMPPPPLLLLEEEESSSS
          To declare an array of pointers to functions like malloc(3),
          do declare fptab as array of pointer to function returning
          pointer to char The result of this command is char
          *(*fptab[])() When you see this declaration in someone
          else's code, you can make sense out of it by doing explain
          char *(*fptab[])() The proper declaration for signal(2)
          cannot be described in _c_d_e_c_l's language (it can't be
          described in C either).  An adequate declaration for most
          purposes is given by declare signal as function returning
          pointer to function returning int The function declaration
          that results has two sets of empty parentheses.  The author
          of such a function might wonder where the parameters go.
          declare signal as function (args) returning pointer to
          function returning int provides the solution: int
          (*signal(args))()

     DDDDIIIIAAAAGGGGNNNNOOOOSSSSTTTTIIIICCCCSSSS
          The declare statement tries to point out constructions that
          are not supported in C.  Also, certain non-portable
          constructs are flagged.

          Syntax errors cause the parser to play dead until a newline
          is read.

     SSSSEEEEEEEE AAAALLLLSSSSOOOO
          Section 8.4 of the C Reference Manual.

     BBBBUUUUGGGGSSSS
          The pseudo-English syntax is excessively verbose.




















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