TCP RFC states that sequence numbers are given to each TCP octet(or byte)

Suppose i use a C function like:
send(sock, msg, len, 0);

where msg is a multi-octet array.

Does the statement mean that for each octet of msg, a separate TCP packet is constructed with its own sequence number?
If not, i.e. only one TCP packet consisting of a TCP header and data(msg) is constructed, how is it that each octet of msg assigned a unique sequence number?

Please clarify