text: #include "buffer.h"
  
  void abAppend(struct abuf* ab, const char* s, int length) {
    char *new = realloc(ab->b, ab->length + length);
    
    if (new == NULL) return;
  
    memcpy(&new[ab->length], s, length);
    ab->b = new;
    ab->length += length;
  } 
  
  void abFree(struct abuf* ab) {
    free(ab->b);
  }