Gamma™ : Version 6.4
	IPC

`locate_task`

locate_task — finds and connects to tasks by name.

Syntax

locate_task (task_name, async_reqd)

Arguments

task_name: The name of the task to locate. The other task must have declared this name through init_ipc or name_attach.
async_reqd: t if locate_task should automatically call init_async_ipc for this task.

Returns

A task if successful, otherwise nil.

Description

This function makes a call to the name locator task for the current operating system. If it finds the named task it makes an IPC connection (in TCP/IP) or creates a virtual circuit (in QNX 4) to that task. If async_reqd is t, then init_async_ipc is also called.

When Gamma locates a task, it returns a printed representation of it, which looks like this: #<Task:10120>. This representation cannot be read back into Gamma, so a symbol is usually assigned when calling locate_task to facilitate refering to or working with a task. We refer to this symbol as the task descriptor. For instance, in the example below, the symbol tsk is the task descriptor.

Example

The two tasks are initiated with init_ipc before calling locate_task.

Task 1:

Gamma> init_ipc("first","Q1");
t
Gamma> getpid();
9231
Gamma> tsk = locate_task("second",nil);
#<Task:9092>
Gamma> send (tsk, #princ("Are you there?\n"));
t
Gamma>

Task 2:

Gamma> init_ipc("second","Q2");
t
Gamma> getpid();
9092
Gamma> next_event
Are you there?
t
Gamma>


isend		locate_task_id

locate_task