Creating a FILE * stream that results in a string

Question

I\'m looking for a way to pass in a FILE * to some function so that the function can write to it with fprintf. This is easy if I want the output t

Answer 1

I'm not sure I understand why you want to mess up with FILE *. Couldn't you simply write to a file and then load it in string?

 char *get_file_in_buf(char *filename) {
   char *buffer;
   ... get file size with fseek or fstat ...
   ... allocate buffer ...
   ... read buffer from file ...
   return buffer;
 }

If you only want to "write" formatted text into a string, another option could be to handle an extensible buffer using snprintf() (see the answers to this SO question for a suggestion on how to handle this: Resuming [vf]?nprintf after reaching the limit).

If, instead, you want to create a type that can be passed transparently to any function taking a FILE * to make them act on string buffers, it's a much more complex matter ...