What is "..." and "##" here?Code:#define INFO(fmt, args...) { SYS_INFO( fmt, ## args ); }
What is "..." and "##" here?Code:#define INFO(fmt, args...) { SYS_INFO( fmt, ## args ); }
Here's gcc's documentation on it: http://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html
gg
Keep in mind it is not standard C or C++. It is an extension specific to gcc.
## is in 6.10.3.3 in ISO/IEC 9899:TC2.
... is also in there spread around.
Last edited by robwhit; 01-02-2008 at 09:01 PM.
You're correct that ## is in the C standards and the C++ standard as a preprocessor directive for token pasting, rob. However, the usage above, which is concerned with defining macros with variable argument lists, is specific to gcc.