On Fri, 2004-11-05 at 11:14 -0500, suresh ds wrote: > Extern variables are understandable. But what are these extern > functions? By default, functions declared in one source file are > visible in another file when these two files are compiled together > (this is what ANSI C says). But at many places in linux source, I see > functions declared with an extern keyword. Does it carry any > significance(to the compiler)? or probably it is just a mechanism to > tell the user reading the file that particular function is defined in > some other file, so don't waste time looking for the function > definition in this file? The latter. It is common practice in more than just the kernel to mark functions that are declared but not defined as extern, giving a hint to both the user and the compiler that the file is defined elsewhere. Of course, the actual exporting rules should remain unchanged. Robert Love -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
