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This is true of all pthread interfaces:  None of the pthread interfaces were intended from inter-process communications; only for inter-pthread communications within the same process (task group).

Roadmap

As alluded to before about the appropriateness of pthread in the OS. There is a roadmap for these kinds of features. That roadmap is to continue to conform strictly to the standard OS definitions of Opengroup.org and to continue to evolve as a fully compliant, very standard, tiny Unix-like operating system.

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