On 6 January 2012 09:28, naveen yadav wrote: > Dear All, > > I want to modify cout source code in GCC such that it will not print > any thing on the screen. > > The reason is I have very large already compile code(distrubited in > lib form) and it is not possible to recompile. so i left with no > option but to modify in GCC code. Will you pls let me know where I can do it . Can't you just redirect the program's output to /dev/null when you run the program? Or close the file descriptor in your program's main() function? Or duplicate the file descriptor in main() to redirect the output to a file? Changing the standard library probably isn't necessary. The relevant code is in libstdc++-v3/src/ios_init.cc