catbuf_len - get number of bytes of data in data buffer
#include <cat.h>
int catbuf_len(cat_buffer *b);
catbuf_len() (macro) returns the total amount of data, as a number of bytes, currently
held in buffer b.
This function, together with catbuf_ch(), cabuf_index(), and
catbuf_pos() are the low-level selectors and modifiers for data buffers.
The number of bytes currently stored in buffer b.
cat, catbuf, catbuf_ch, catbuf_index, catbuf_pos