Privatae
24 lines
692 B
Go
24 lines
692 B
Go
//go:build !windows
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package main
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import (
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"os"
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"golang.org/x/sys/unix"
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)
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// flockFile takes an exclusive advisory lock on f (blocking). Released by
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// closing f. Advisory is enough: every writer of a pairing file is this
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// binary, and every one of them goes through withPairingsLock.
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func flockFile(f *os.File) error {
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return unix.Flock(int(f.Fd()), unix.LOCK_EX)
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}
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// flockFileNB is flockFile without the wait: it fails immediately when another
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// process holds the lock, so an interactive `run` can say "already running"
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// instead of hanging as an invisible standby (singleton.go).
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func flockFileNB(f *os.File) error {
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return unix.Flock(int(f.Fd()), unix.LOCK_EX|unix.LOCK_NB)
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}
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