[MESOS-9804] Subprocess should close inherited file descriptors earlier.

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Not A Problem
• Component/s: libprocess
• Assignee: Unassigned
• Reporter: James Peach
• Created: 31/May/19 04:56
• Updated: 17/Jun/19 06:55
• Resolved: 17/Jun/19 06:55

Description

The libprocess subprocess API doesn't close the file descriptors that are inherited across fork until after applying the child hooks. This means that the inherited descriptors can remain open for much longer than you expect, since parent and child hooks both need to be scheduled and run.

We should move the file descriptor closing as early as possible in the child. We might also consider having the child write a byte back to the parent so that we have a guaranteed synchronization point.