Llew_Llaw_Gyffes:

Generally I don't let multiple threads talk to the terminal, mostly because of the problems you're experiencing right now. Instead, I tend to let asynchronous tasks add their complete messages to a queue, and have one thread (usually the one starting all the others) poll the queues and print messages.

The primary difficulties of sharing a terminal with multiple writers is due to (1) buffering (see suffering from buffering), and (2) you can task switch in the *middle* of an escape sequence. So you get text out of the expected sequence, and in the wrong locations and colors due to the broken escape sequences.

If you give each thread an array that they can put complete messages into, and have one thread grabbing distinct messages and printing them, you can more easily manage your terminal.

...roboticus

When your only tool is a hammer, all problems look like your thumb.

Update: Corrected name.

In reply to Re: Semaphores failing to prevent race condition by roboticus
in thread Semaphores failing to prevent race condition by Llew_Llaw_Gyffes

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