How does Fiasco implement printf

Adam Lackorzynski adam at
Sun Jun 22 23:29:37 CEST 2014


On Fri Jun 20, 2014 at 17:11:21 -0400, Yuxin Ren wrote:
> I think printf usually invoke system call. But in Fiasco only one system
> call is capability invocation. So what capability is invoked by printf? Or
> Fiasco implements printf in user level, so printf triggers a normal IPC?

Since capability invocation and IPC is the same it's actually both.
Each task has a 'log' capability which is used to print out text. printf
and friends also uses this interface pass on output.

Adam                 adam at

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