#include <stdlib.h>
#include <unistd.h>

extern void do_something(char *s);

void process_something(int size) {
  int fd;
    
  // Catch integer overflow.
  if (size > size+1)
    abort();

  // Error checking from this code elided.
  char *string = malloc(size+1);
  read(fd, string, size);
  string[size] = 0;
  do_something(string);
  free(string);
}