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C functions, declaration scope, and externals?

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The Question is:

 
This is  for C.
 
Is it possible to use the same variable name defined by the system h files
and redefine it of diff type in my local program.
 
For example index is defined in string.h
as
char *index
 
in my local program I have index defined as
long index.
 
And stingh.h is one of the include files
Compiler gives an error saying not compatable
 
How can I get around this
thanks
 
 

The Answer is :

 
  Duplicating variables with declarations from the header files or from
  the C standard library is inadvisable practice.  If you wish to perform
  this practice, you will want to comment your code clearly, and become
  familiar with the scope rules used for the declaration of and the use
  of variables.
 
  The particular declaration you reference in string.h is the index
  function, not the index variable.  It would also appear your variable
  may be of external scope.  Recent versions of C allow you to have
  external variables that overlap function names, though the Wizard
  still views this practice as inadvisable.  Prior to the versions with
  separate scopes, you will want to use the /PREFIX qualifier to suppress
  the prefix on the specified external variable.
 
  When posting a question such as this, please include the relevent
  product versions such as the compiler version, a short reproducer, and
  the complete text of the error message(s) generated.
 

  

     

     
answer written or last revised on ( 27-JAN-1999 )
     
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