Maxim Integrated High-Speed Microcontroller Users Guide: Network Microcontroller Supplement User Manual
Page 197
High-Speed Microcontroller User’s
Guide: Network Microcontroller
Supplement
197
recvfrom
Description:
int recvfrom(
int s,
/* receive on socket with handle s */
void *buf,
/* datagram data array at *buf */
int len,
/* size of datagram received */
int flags,
/* currently ignored */
struct sockaddr *addr,
/* remote address */
int addrlen);
/* size of address structure */
The
recvfrom function receives a UDP datagram. This function receives a message on socket s, storing the message at *buf.
len is the size of buf. If addr is not NULL, the remote address is filled in at *addr. The flags parameter is ignored.
recvfrom
returns the number of bytes read. If no data is available on the socket,
recvfrom blocks for the amount of time specified with
the
setsockopt/SO_TIMEOUT call. Note: It is generally required to use bind in order to first assign a local port to the socket.
connect
Description:
int connect(
int s,
/* socket to connect to a specific address */
struct sockaddr *addr,
/* address to which socket s should be connected */
int addrlen);
/* size of address structure */
The
connect function connects a TCP socket to the specified address. This function connects the sockets to the remote
address specified by the addr structure and returns a success/failure code in the accumulator.
Connect can only be used
once with each socket.
bind
Description:
int bind(
int s,
/* socket to bind to specified address/port */
struct sockaddr *addr,
/* address to which socket s should be bound */
int addrlen);
/* length of addr structure */
The
bind function binds a socket to the specified address. This function assigns a local address and port at *addr to the sock-
et s. The combination of IP address and port is often referred to as “name.” Binding a socket is necessary for server sockets.
For client sockets, use
bind if a specific source port is requested. Socket s is to be assigned a local name, addr contains the
local address (IP and port values). The
bind function returns a success/failure code in the accumulator.
INPUT
PARAMETER#–DESCRIPTION
OUTPUT
DESCRIPTION
s
*addr
addrlen
Param0[0]–socket handle #
Param1[0:2]–pointer to target addr
Param2[0]–size of addr structure
ACC
Return value (= 0 for success)
INPUT
PARAMETER#–DESCRIPTION
OUTPUT
DESCRIPTION
s
*addr
addrlen
Param0[0]–socket handle #
Param1[0:2]–pointer to target addr
Param2[0]–size of addr structure
ACC
Return value (= 0 for success)
INPUT
PARAMETER#–DESCRIPTION
OUTPUT
DESCRIPTION
s
*buf
len
flags
*addr
addrlen
Param0[0]–socket handle #
Param1[0:2]–pointer to UDP data
Param2[0:1]–size of datagram
Param3–currently ignored
Param4[0:2]–pointer to target addr
Param5[0]–size of addr structure
ACC
R1:R0
Return value (= 0 for success)
Number of bytes received
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