Winston at 21:07, 28 March 2008

2008-03-28T21:07:59Z

← Older revision		Revision as of 22:07, 28 March 2008
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	ld c, SOCK_STREAM ; A reliable stream - TCP		ld c, SOCK_STREAM ; A reliable stream - TCP
	ld hl, ~~0x3E00~~ ; Call table for socket()		ld hl, SOCKET ; Call table for socket() - 0x3E00
	call HLCALL ; Trigger ROM page in		call HLCALL ; Trigger ROM page in
	bit 7, a ; Check for a negative return code (MSB set)		bit 7, a ; Check for a negative return code (MSB set)

Winston: Experiment with documentation format for function calls

2008-03-28T21:05:48Z

Experiment with documentation format for function calls

New page

'''socket (HLCALL 0x3E00) ''' - Create an end point for communication.

== Synopsis ==

''Assembly language''

ld c, socket_type
ld hl, 0x3E00
call HLCALL

''C''

int socket(int domain, int type, int protocol);

The '''socket''' function opens an end point for communication, and returns a file descriptor on success. Only AF_INET sockets are supported. In the C interface, the domain and protocol parameters are provided for compatibility with the BSD socket library and are ignored. The protocol parameter should be set to zero; it is very possible that the protocol parameter will be used in a later release of the library.

The socket function allocates the resources required to communicate. It allocates a descriptor ('socket handle'), and associates this with the appropriate hardware registers.

== Return value ==

On success, a file descriptor for the new socket is returned in the A register (asm interface) or as the return code (C interface). On error, the asm interface returns the error code in A, and the C interface returns -1 and sets errno to the error number.

== Examples ==

The following example shows how to open a socket that will be used for a TCP connection (either one that listens for incoming connections, or will be used to connect to a remote host). The socket() function just opens the socket - it doesn't decide whether it's to be used for a server or client connection. To open a UDP connection, the type parameter should be set to SOCK_DGRAM.

Assembly language:

ld c, SOCK_STREAM ; A reliable stream - TCP
ld hl, 0x3E00 ; Call table for socket()
call HLCALL ; Trigger ROM page in
bit 7, a ; Check for a negative return code (MSB set)
jr nz, .handle_error ; failed to allocate a socket if the return code < 0

; at this point, A contains the file descriptor (aka socket handle)

C:

int sock;
sock=socket(AF_INET, SOCK_STREAM, 0);
if(sock > 0)
{
/* socket opened successfully, do something */
}
else
{
/* handle the error */
}

[[Category:Spectranet]]

Socket - Revision history

Winston at 21:07, 28 March 2008

Winston: Experiment with documentation format for function calls