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1bfbee0e20
Done with: go get go@1.18 go mod tidy go fix ./... Using go1.21.3. Also update code generators to use only the new go:build lines, not the old +build ones. For golang/go#60268. Change-Id: I6aabc42efb6ab3329981100e1db2263aac5e92a6 Reviewed-on: https://go-review.googlesource.com/c/sys/+/534222 Reviewed-by: Ian Lance Taylor <iant@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
51 lines
1.3 KiB
Go
51 lines
1.3 KiB
Go
// Copyright 2021 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:build (darwin && !ios) || (linux && !android)
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package unix_test
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import (
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"log"
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"golang.org/x/sys/unix"
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)
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func ExampleSysvShmGet() {
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// create shared memory region of 1024 bytes
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id, err := unix.SysvShmGet(unix.IPC_PRIVATE, 1024, unix.IPC_CREAT|unix.IPC_EXCL|0o600)
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if err != nil {
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log.Fatal("sysv shm create failed:", err)
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}
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// warning: sysv shared memory segments persist even after after a process
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// is destroyed, so it's very important to explicitly delete it when you
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// don't need it anymore.
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defer func() {
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_, err := unix.SysvShmCtl(id, unix.IPC_RMID, nil)
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if err != nil {
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log.Fatal(err)
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}
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}()
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// to use a shared memory region you must attach to it
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b, err := unix.SysvShmAttach(id, 0, 0)
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if err != nil {
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log.Fatal("sysv attach failed:", err)
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}
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// you should detach from the segment when finished with it. The byte
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// slice is no longer valid after detaching
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defer func() {
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if err = unix.SysvShmDetach(b); err != nil {
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log.Fatal("sysv detach failed:", err)
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}
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}()
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// Changes to the contents of the byte slice are reflected in other
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// mappings of the shared memory identifer in this and other processes
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b[42] = 'h'
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b[43] = 'i'
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}
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