Class BasicSocket
In: socket/socket.c
Parent: IO

Methods

Public Class methods

do_not_reverse_lookup()
do_not_reverse_lookup=(p1)
for_fd(p1)

Public Instance methods

close_read()
close_write()
getpeername()
getsockname()

Gets a socket option. These are protocol and system specific, see your local sytem documentation for details. The option is returned as a String with the data being the binary value of the socket option.

Parameters

  • level is an integer, usually one of the SOL_ constants such as Socket::SOL_SOCKET, or a protocol level.
  • optname is an integer, usually one of the SO_ constants, such as Socket::SO_REUSEADDR.

Examples

Some socket options are integers with boolean values, in this case getsockopt could be called like this:

  optval = sock.getsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR)
  optval = optval.unpack "i"
  reuseaddr = optval[0] == 0 ? false : true

Some socket options are integers with numeric values, in this case getsockopt could be called like this:

  optval = sock.getsockopt(Socket::IPPROTO_IP, Socket::IP_TTL)
  ipttl = optval.unpack("i")[0]

Option values may be structs. Decoding them can be complex as it involves examining your system headers to determine the correct definition. An example is a +struct linger+, which may be defined in your system headers as:

  struct linger {
    int l_onoff;
    int l_linger;
  };

In this case getsockopt could be called like this:

  optval =  sock.getsockopt(Socket::SOL_SOCKET, Socket::SO_LINGER)
  onoff, linger = optval.unpack "ii"

[Source]

/*
 * Document-method: getsockopt
 * call-seq: getsockopt(level, optname)
 *
 * Gets a socket option. These are protocol and system specific, see your
 * local sytem documentation for details. The option is returned as
 * a String with the data being the binary value of the socket option.
 *
 * === Parameters
 * * +level+ is an integer, usually one of the SOL_ constants such as
 *   Socket::SOL_SOCKET, or a protocol level.
 * * +optname+ is an integer, usually one of the SO_ constants, such
 *   as Socket::SO_REUSEADDR.
 *
 * === Examples
 *
 * Some socket options are integers with boolean values, in this case
 * #getsockopt could be called like this:
 *   optval = sock.getsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR)
 *   optval = optval.unpack "i"
 *   reuseaddr = optval[0] == 0 ? false : true
 *
 * Some socket options are integers with numeric values, in this case
 * #getsockopt could be called like this:
 *   optval = sock.getsockopt(Socket::IPPROTO_IP, Socket::IP_TTL)
 *   ipttl = optval.unpack("i")[0]
 *
 * Option values may be structs. Decoding them can be complex as it involves
 * examining your system headers to determine the correct definition. An
 * example is a +struct linger+, which may be defined in your system headers
 * as:
 *   struct linger {
 *     int l_onoff;
 *     int l_linger;
 *   };
 * 
 * In this case #getsockopt could be called like this:
 *   optval =  sock.getsockopt(Socket::SOL_SOCKET, Socket::SO_LINGER)
 *   onoff, linger = optval.unpack "ii"
*/
static VALUE
bsock_getsockopt(sock, lev, optname)
    VALUE sock, lev, optname;
{
#if !defined(__BEOS__)
    int level, option;
    socklen_t len;
    char *buf;
    OpenFile *fptr;

    level = NUM2INT(lev);
    option = NUM2INT(optname);
    len = 256;
    buf = ALLOCA_N(char,len);
    GetOpenFile(sock, fptr);

    GetOpenFile(sock, fptr);
    if (getsockopt(fileno(fptr->f), level, option, buf, &len) < 0)
	rb_sys_fail(fptr->path);

    return rb_str_new(buf, len);
#else
    rb_notimplement();
#endif
}
recv(...)
send(...)

Sets a socket option. These are protocol and system specific, see your local sytem documentation for details.

Parameters

  • level is an integer, usually one of the SOL_ constants such as Socket::SOL_SOCKET, or a protocol level.
  • optname is an integer, usually one of the SO_ constants, such as Socket::SO_REUSEADDR.
  • optval is the value of the option, it is passed to the underlying setsockopt() as a pointer to a certain number of bytes. How this is done depends on the type:
    • Fixnum: value is assigned to an int, and a pointer to the int is passed, with length of sizeof(int).
    • true or false: 1 or 0 (respectively) is assigned to an int, and the int is passed as for a Fixnum. Note that false must be passed, not nil.
    • String: the string’s data and length is passed to the socket.

Examples

Some socket options are integers with boolean values, in this case setsockopt could be called like this:

  sock.setsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR, true)

Some socket options are integers with numeric values, in this case setsockopt could be called like this:

  sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_TTL, 255)

Option values may be structs. Passing them can be complex as it involves examining your system headers to determine the correct definition. An example is an ip_mreq, which may be defined in your system headers as:

  struct ip_mreq {
    struct  in_addr imr_multiaddr;
    struct  in_addr imr_interface;
  };

In this case setsockopt could be called like this:

  optval =  IPAddr.new("224.0.0.251") + Socket::INADDR_ANY
  sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_ADD_MEMBERSHIP, optval)

[Source]

/*
 * Document-method: setsockopt
 * call-seq: setsockopt(level, optname, optval)
 *
 * Sets a socket option. These are protocol and system specific, see your
 * local sytem documentation for details.
 *
 * === Parameters
 * * +level+ is an integer, usually one of the SOL_ constants such as
 *   Socket::SOL_SOCKET, or a protocol level.
 * * +optname+ is an integer, usually one of the SO_ constants, such
 *   as Socket::SO_REUSEADDR.
 * * +optval+ is the value of the option, it is passed to the underlying
 *   setsockopt() as a pointer to a certain number of bytes. How this is
 *   done depends on the type:
 *   - Fixnum: value is assigned to an int, and a pointer to the int is
 *     passed, with length of sizeof(int).
 *   - true or false: 1 or 0 (respectively) is assigned to an int, and the
 *     int is passed as for a Fixnum. Note that +false+ must be passed,
 *     not +nil+.
 *   - String: the string's data and length is passed to the socket.
 *
 * === Examples
 *
 * Some socket options are integers with boolean values, in this case
 * #setsockopt could be called like this:
 *   sock.setsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR, true)
 *
 * Some socket options are integers with numeric values, in this case
 * #setsockopt could be called like this:
 *   sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_TTL, 255)
 *
 * Option values may be structs. Passing them can be complex as it involves
 * examining your system headers to determine the correct definition. An
 * example is an +ip_mreq+, which may be defined in your system headers as:
 *   struct ip_mreq {
 *     struct  in_addr imr_multiaddr;
 *     struct  in_addr imr_interface;
 *   };
 * 
 * In this case #setsockopt could be called like this:
 *   optval =  IPAddr.new("224.0.0.251") + Socket::INADDR_ANY
 *   sock.setsockopt(Socket::IPPROTO_IP, Socket::IP_ADD_MEMBERSHIP, optval)
 *
*/
static VALUE
bsock_setsockopt(sock, lev, optname, val)
    VALUE sock, lev, optname, val;
{
    int level, option;
    OpenFile *fptr;
    int i;
    char *v;
    int vlen;

    rb_secure(2);
    level = NUM2INT(lev);
    option = NUM2INT(optname);

    switch (TYPE(val)) {
      case T_FIXNUM:
	i = FIX2INT(val);
	goto numval;
      case T_FALSE:
	i = 0;
	goto numval;
      case T_TRUE:
	i = 1;
      numval:
	v = (char*)&i; vlen = sizeof(i);
	break;
      default:
	StringValue(val);
	v = RSTRING(val)->ptr;
	vlen = RSTRING(val)->len;
	break;
    }

    GetOpenFile(sock, fptr);
    if (setsockopt(fileno(fptr->f), level, option, v, vlen) < 0)
	rb_sys_fail(fptr->path);

    return INT2FIX(0);
}
shutdown(...)

[Validate]