Channel

Syntax

channel[a,b]

Where a and b are both distinct processes which the channel will connect.

Semantics

The channel type will specify that a variable is a channel from process a (sender) to process b (receiver.) Normally this will result in synchronous communication, although if the async type is used then asynchronous communication is selected instead. Note that channel is unidirectional, where process a sends and b receives, NOT the otherway around.

Note: By default (no further type information) all channel communication is blocking using standard send.
Note: If no allocation information is specified with the channel type then the underlying variable will not be assigned any memory - it is instead an abstract connection in this case.

Example

var x:Int::allocated[multiple[]];
var p;
par p from 0 to 2 {
   (x::channel[0,2]):=193;
   var hello:=(x::channel[0,2]);
};

In this case, x is a channel between processes 0 and 2. In the par loop process 0 sends the value 193 to process 2. Then the variable hello is declared and process 2 will receive this value.