gethostbyname

Resolve host name.

Syntax

ip = gethostbyname(host)

Description

gethostbyname(host) gives the IP address of host in dot notation as a string.

Example

gethostbyname('localhost')
  127.0.0.1

See also

gethostname

gethostname

Get name of current host.

Syntax

str = gethostname

Description

gethostname gives the name of the current host as a string.

See also

gethostbyname

socketaccept

Accept a connection request.

Syntax

fd = socketaccept(fds)

Description

socketaccept(fds) accepts a new connection requested by a client to the server queue created with socketservernew. Its argument fds is the file descriptor returned by socketservernew.

Once a connection has been opened, the file descriptor fd can be used with functions such as fread, fwrite, fscanf, and fprintf. The connection is closed with fclose.

See also

fclose, socketconnect, socketservernew, fread, fwrite, fscanf, fgetl, fgets, fprintf

socketconnect

Change UDP connection.

Syntax

socketconnect(fd, hostname, port)

Description

socketconnect(fd,hostname,port) changes the remote host and port of the UDP connection specified by fd. An attempt to use socketconnect on a TCP connection throws an error.

See also

socketnew

socketnew

Create a new connection to a server.

Syntax

fd = socketnew(hostname, port, options)
fd = socketnew(hostname, port)

Description

socketnew(hostname,port) creates a new TCP connection to the specified hostname and port and returns a file descriptor fd.

The third argument of socketnew(hostname,port,options) is a structure which contains configuration settings. It is set with socketset.

Once a connection has been opened, the file descriptor fd can be used with functions such as fread, fwrite, fscanf, and fprintf. The connection is closed with fclose.

Example

fd = socketnew('www.somewebserver.com', 80, ...
       socketset('TextMode',true));
fprintf(fd, 'GET %s HTTP/1.0\n\n', '/');
reply = fgets(fd)
  reply =
    HTTP/1.1 200 OK
fclose(fd);

See also

fclose, socketset, socketconnect, socketservernew, fread, fwrite, fscanf, fgetl, fgets, fprintf

socketservernew

Create a new server queue for accepting connections from clients.

Syntax

fds = socketservernew(port, options)
fds = socketservernew(port)

Description

socketservernew(hostname,port) creates a new TCP or UDP socket for accepting incoming connections. Connections from clients are accepted with socketaccept, which must provide as input argument the file descriptor returned by socketservernew. Using multiple threads, multiple connections can be accepted on the same port, using multiple socketaccept for one socketservernew.

The second argument of socketservernew(port,options) is a structure which contains configuration settings. It is set with socketset. Options are inherited by the connections established with socketaccept. On platforms where administrator authorizations are enforced, only an administrator account (root account) can listen to a port below 1024. Only one server can listen to the same port.

To stop listening to new connections, the socket is closed with fclose. The file descriptor returned by socketservernew can be used only with socketaccept and fclose.

Example

fds = socketservernew(8080);
fd = socketaccept(fds);
request = fscanf(fd, 'GET %s');
fprintf(fd, 'Your request is "%s"\n', request);
fclose(fd);
fclose(fds);

See also

fclose, socketset, socketaccept, socketnew

socketset

Configuration settings for sockets.

Syntax

options = socketset
options = socketset(name1=value1, ...)
options = socketset(name1, value1, ...)
options = socketset(options0, name1, value1, ...)

Description

socketset(name1,value1,...) creates the option argument used by socketnew and socketservernew. Options are specified with name/value pairs, where the name is a string which must match exactly the names in the table below. Case is significant. Alternatively, options can be given with named arguments. Options which are not specified have a default value. The result is a structure whose fields correspond to each option. Without any input argument, socketset creates a structure with all the default settings. Note that socketnew also interprets the lack of an option argument, or the empty array [], as a request to use the default values.

When its first input argument is a structure, socketset adds or changes fields which correspond to the name/value pairs which follow.

Here is the list of permissible options:

Name	Default	Meaning
ListenQueue	5	queue size for incoming connections
Proto	'tcp'	protocol ('tcp' or 'udp')
TextMode	true	text mode
Timeout	30	timeout in seconds

When TextMode is true, input CR and CR-LF sequences are converted to LF, and output LF is converted to CR-LF, to follow the requirements of many Internet protocols where lines are separated with CR-LF. Note that TextMode is true by default.

Example

socketset
  ListenQueue: 5
  Proto: 'tcp'
  TextMode: true
  Timeout: 30

See also

socketnew, socketservernew, socketsetopt

socketsetopt

Settings change for sockets.

Syntax

socketsetopt(fd, name1=value1, ...)
socketsetopt(fd, name1, value1, ...)
socketsetopt(fd, options)

Description

socketsetopt(fd,name1,value1,...) changes the options for the socket identified by fd. Options are specified by pairs of name and value. They are the same as those valid with socketset. However, only TextMode and Timeout have an effect; other ones are ignored.

socketsetopt(fd,options) takes as second argument a structure of options created with socketset.

See also

socketset, socketnew, socketservernew