Question

I am trying to pass on a list of arguments to sprintf which apparently doens’t pick them up. What am i missing?

void respond( const char *format, ...) {
  char buffer[256];
  va_list args;
  int len, retCode;

  va_start( args, format);
  len = sprintf( buffer, format, args);
  va_end( args);

  retCode = send( newSockFD, buffer, len, 0);
  if( retCode == -1) error( "Could not write to socket");
}

Answer 1

sprintf can not work with varable argument so use

vsnprintf()

 len = vsnprintf( buffer, sizeof(buffer),format, args);