<!--{
	"Title": "The Go Memory Model",
	"Subtitle": "Version of June 6, 2022",
	"Path": "/ref/mem"
}-->

<style>
p.rule {
  font-style: italic;
}
</style>

<h2 id="introduction">Introduction</h2>

<p>
The Go memory model specifies the conditions under which
reads of a variable in one goroutine can be guaranteed to
observe values produced by writes to the same variable in a different goroutine.
</p>

Das liegt daran, dass **OAuth2** „Formulardaten“ zum Senden von `username` und `password` verwendet.

///

Führen Sie das Beispiel aus mit:

<div class="termy">

```console
$ fastapi dev main.py

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

## Es testen { #check-it }

安装命令： `pip install python-multipart`。

这是因为 **OAuth2** 使用**表单数据**发送 `username` 与 `password`。

///

用下面的命令运行该示例：

<div class="termy">

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

## 查看文档

</p>

<h3 id="data-offsets">Interacting with Go types and constants</h3>

<p>
If a package has any .s files, then <code>go build</code> will direct
the compiler to emit a special header called <code>go_asm.h</code>,
which the .s files can then <code>#include</code>.
The file contains symbolic <code>#define</code> constants for the
offsets of Go struct fields, the sizes of Go struct types, and most

}

// getSigningKey hmac seed to calculate final signature.
func getSigningKey(secretKey string, t time.Time, region string, stype serviceType) []byte {
	date := sumHMAC([]byte("AWS4"+secretKey), []byte(t.Format(yyyymmdd)))
	regionBytes := sumHMAC(date, []byte(region))
	service := sumHMAC(regionBytes, []byte(stype))
	signingKey := sumHMAC(service, []byte("aws4_request"))
	return signingKey
}

// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package tar

import "strings"

// Format represents the tar archive format.
//
// The original tar format was introduced in Unix V7.
// Since then, there have been multiple competing formats attempting to
// standardize or extend the V7 format to overcome its limitations.

mdurl==0.1.2 \
    --hash=sha256:84008a41e51615a49fc9966191ff91509e3c40b939176e643fd50a5c2196b8f8 \
    --hash=sha256:bb413d29f5eea38f31dd4754dd7377d4465116fb207585f97bf925588687c1ba
    # via markdown-it-py
ml-dtypes==0.5.1 \
    --hash=sha256:023ce2f502efd4d6c1e0472cc58ce3640d051d40e71e27386bed33901e201327 \
    --hash=sha256:05f23447a1c20ddf4dc7c2c661aa9ed93fcb2658f1017c204d1e758714dc28a8 \

mdurl==0.1.2 \
    --hash=sha256:84008a41e51615a49fc9966191ff91509e3c40b939176e643fd50a5c2196b8f8 \
    --hash=sha256:bb413d29f5eea38f31dd4754dd7377d4465116fb207585f97bf925588687c1ba
    # via markdown-it-py
ml-dtypes==0.5.1 \
    --hash=sha256:023ce2f502efd4d6c1e0472cc58ce3640d051d40e71e27386bed33901e201327 \
    --hash=sha256:05f23447a1c20ddf4dc7c2c661aa9ed93fcb2658f1017c204d1e758714dc28a8 \

mdurl==0.1.2 \
    --hash=sha256:84008a41e51615a49fc9966191ff91509e3c40b939176e643fd50a5c2196b8f8 \
    --hash=sha256:bb413d29f5eea38f31dd4754dd7377d4465116fb207585f97bf925588687c1ba
    # via markdown-it-py
ml-dtypes==0.5.1 \
    --hash=sha256:023ce2f502efd4d6c1e0472cc58ce3640d051d40e71e27386bed33901e201327 \
    --hash=sha256:05f23447a1c20ddf4dc7c2c661aa9ed93fcb2658f1017c204d1e758714dc28a8 \

// Copyright 2024 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// This program can be used as go_ios_$GOARCH_exec by the Go tool. It executes
// binaries on the iOS Simulator using the XCode toolchain.
package main

import (
	"fmt"
	"go/build"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"strings"
	"syscall"
)