buffer_get_token_sa - read token from buffer
#include <libowfat/stralloc.h>
#include <libowfat/buffer.h>
int buffer_get_token_sa(buffer* b,stralloc* sa,
const char* charset,size_t setlen);
buffer_get_token_sa appends data from the b to sa until one of the
delimiters in charset is found, NOT overwriting the previous content of
sa. That delimiter is also appended to sa.
If reading from the buffer or allocating memory fails,
buffer_get_token_sa returns -1 and sets errno appropriately. At that
point sa may already contain a partial token.
-1 on error (setting errno), 0 on EOF, 1 when successful.
buffer_get_token_sa appends instead of overwriting so it can be used on
non-blocking sockets (these signal error and set errno to EAGAIN; in
this case you can simply call buffer_get_token_sa again when select or
poll indicate more data is available).
buffer_getline_sa(3), buffer_get_token(3), buffer(3)