Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!decwrl!ucbvax!tct.UUCP!chip
From: chip@tct.UUCP (Chip Salzenberg)
Newsgroups: comp.lang.c++
Subject: System headers automatically extern "C"
Message-ID: <m0i1kSI-0001IRC@tct.uucp>
Date: 13 Aug 90 19:28:08 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 35

I like to include the stanard system header files from /usr/include in
my C++ programs.  However, I get tired of having to bracket them with
'extern "C" {}' every time.  I thus applied the following, very simple
change to cplus-lex.c.  With this change, all filenames that begin
with the string STANDARD_INCLUDE ("/usr/include/" on my system) are
implicitly bracketed with 'extern "C"'.

Note that you must include an appropriate definition of STANDARD_INCLUDE
in your Makefile or in your configuration header file.
*** cplus-lex.c.Q	Thu Jul 26 11:02:07 1990
--- cplus-lex.c	Thu Aug  9 12:50:10 1990
***************
*** 2053,2056 ****
--- 2053,2061 ----
  	      input_file_stack = p;
  	      input_file_stack_tick++;
+ #ifdef STANDARD_INCLUDE
+ 	      if (strncmp(p->name, STANDARD_INCLUDE,
+ 			  sizeof(STANDARD_INCLUDE) - 1) == 0)
+ 		push_lang_context(lang_name_c);
+ #endif
  	    }
  	  else if (input_file_stack->next)
***************
*** 2057,2060 ****
--- 2062,2070 ----
  	    {
  	      struct file_stack *p = input_file_stack;
+ #ifdef STANDARD_INCLUDE
+ 	      if (strncmp(p->name, STANDARD_INCLUDE,
+ 			  sizeof(STANDARD_INCLUDE) - 1) == 0)
+ 		pop_lang_context();
+ #endif
  	      input_file_stack = p->next;
  	      free (p);