Linux socket (1)

Linux socket (1)

Socket features are determined by three attributes: domain, type, and protocol.

1. Domain

AF_UNIX UNIX domain protocol (File System socket)

AF_INET ARPA Internet Protocol (UNIX network socket)

... Omitted

2. Type

1) stream socket: SOCK_STREAM

2) datagram socket: SOCK_DGRAM

3. Protocol

Generally, this parameter is determined by the socket type and socket domain. You do not need to select this parameter. setting this parameter to 0 indicates that the default protocol is used.

Socket address.

1) AF_UNIX

Struct sockaddr_un {

Sa_family_t sun_family;/* AF_UNIX */

Char sun_path [];/* pathname */

};

2) AF_INET

Struct sockaddr_in {

Short int sin_family;/* AF_INET */

Unsigned short int sin_port;/* port number */

Struct in_addr sin_addr;/* Internet address */

}; This structure is defined in the header file netinet/in. h.

The IP address structure in_addr is defined:

Struct in_addr {

Unsigned long int s_addr;

};

1. Named socket

# Include <sys/socket. h>

Int bind (int socket, const struct sockaddr * address, size_t address_len );

2. Create a socket queue

# Include <sys/socket. h>

Int listen (int socket, int backlog );

3. Accept connections

# Include <sys/socket. h>

Int accept (int socket, struct sockaddr * address, size_t * address_len );

4. Request connection

# Include <sys/socket. h>

Int connect (int socket, const struct sockaddr * address, size_t address_len );

5. Disable socket

Close ();