[1] : The Free On-line Dictionary of Computing (27 SEP 03)

c preprocessor
     
         cpp the standard unix
        macro-expansion utility run as the first phase of the c
        compiler, cc.  cpp interprets lines beginning with "" such
        as
     
        	define buffer_size 256
     
        as a textual assignment giving the symbol buffer_size a
        value "256".  symbols defined with cpp are traditionally given
        upper case names to distinguish them from c identifiers.  this
        symbol can be used later in the input, as in
     
        	char input_bufferbuffer_size;
     
        this use of cpp to name constants, rather than writing these
        magic numbers inline, makes a program easier to read and
        maintain, especially if there is more than one occurrence of
        buffer_size all of which must all have the same value.
     
        cpp macros can have parameters:
     
        	define bitn 1<compile time.
     
        decus cpp is a free implementation for vms.
     
        the most widely used c preprocessor today is the gnu cpp,
        distributed as part of gcc.
     
        2001-12-31
     
     
see also:
unix macro c cc assignment magic numbers 
compile time decus cpp vms gnu gcc 

Preprocessor >> P Words
Preprocessor, definition of term: Preprocessor
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