I have a function like this: write_f(par1,par2,"ababsbsbsbs %Wtralari sdfdfsdf",va_list arguments); Function replaces %Wtralari with a output of function tralari return array of chars, this function need six parameters, I pass this parameters with va_list of write_f. /* I use this because out of tralari can not be passed to write_f in va_list */ The problem is that I always have a mistake with type or number of parameters, and segfault or something like this. It's posible make something for GCC parse my function?