socket_connect6(3) attempt to make a TCP connection


#include <socket.h>

int socket_connect6(int s, const char ip[16],
                    uint16 port,uint32 scope_id);


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.


  #include <socket.h>

  int s;
  char ip[16];
  uint16 p;

  s = socket_tcp6();