table of contents
socket_connect6(3) | Library Functions Manual | socket_connect6(3) |
NAME¶
socket_connect6 - attempt to make a TCP connection
SYNTAX¶
#include <libowfat/socket.h>
int socket_connect6(int s, const char ip[16],
uint16 port,uint32 scope_id);
DESCRIPTION¶
socket_connect6 attempts to make a connection from TCP socket s to TCP port port on IP address ip.
The meaning of scope_id is dependent on the implementation and IPv6 IP. On link-local IPv6 addresses it specifies the outgoing interface index. The name (e.g. "eth0") for a given interface index can be queried with getifname. scope_id should normally be set to 0.
socket_connect6 may return
- 0, to indicate that the connection succeeded (and succeeded immediately, if the socket is non-blocking)
- -1, setting errno to error_inprogress or error_wouldblock, to indicate that the socket is non-blocking
- -1, setting errno to something else, to indicate that the connection failed (and failed immediately, if the socket is non-blocking).
When a background connection succeeds or fails, s becomes writable; you can use socket_connected to see whether the connection succeeded. If the connection failed, socket_connected returns 0, setting errno appropriately.
Once a TCP socket is connected, you can use the read and write system calls to transmit data.
You can call socket_connect6 without calling socket_bind6. This has the effect as first calling socket_bind6 with IP address :: and port 0.
EXAMPLE¶
#include <libowfat/socket.h>
int s;
char ip[16];
uint16 p;
s = socket_tcp6();
socket_bind6(s,ip,p);
socket_connect6(s,ip,p,0);
SEE ALSO¶
socket_connect4(3), socket_fastopen_connect6(3), socket_getifname(3)