Thanks a lot Jonathan, it works for me .. On Sat, Jan 7, 2012 at 5:32 PM, Jonathan Wakely <jwakely.gcc@xxxxxxxxx> wrote: > On 7 January 2012 06:49, naveen yadav wrote: >> Thanks a lot Jonathan, >> >> The reason for modifying stdlib is needed because i do not have source >> code of binary which i want to test. >> will you pls let me know execty lines in ios_init.cc which I need to >> modify , this will help me a lot. > > Put > std::cout.setstate(ios_base::failbit); > > after cout has been constructed, so around line 102 > > >> Thanks >> >> On Fri, Jan 6, 2012 at 6:25 PM, Jonathan Wakely <jwakely.gcc@xxxxxxxxx> wrote: >>> On 6 January 2012 12:41, naveen yadav wrote: >>>> The reason is that is we want to check effect of cout on application booting. >>>> Below is simple hello world program, It still call write() system >>>> call. This may delay if >>>> we have lots of cout in applications. >>>> so we want that cout simply return without call of write(). >>> >>> std::cout.setstate(ios_base::failbit); >>> >>> If you do that at the top of main() it will prevent any writes to >>> cout. If your library writes to cout before main() starts, you could >>> put that in a global object's constructor (and use >>> __attribute__((init_priority(101))) to make it run before other global >>> constructors) >>> >>> Or if you really insist on modifying the stdlib, do that in >>> ios_init.cc in ios_base::Init::Init() (not in sync_with_stdio, that's >>> the wrong place)
