## Зависимости для групп *операций пути*

	SIGTTOU   = C.SIGTTOU
	SIGURG    = C.SIGURG
	SIGXCPU   = C.SIGXCPU
	SIGXFSZ   = C.SIGXFSZ
	SIGVTALRM = C.SIGVTALRM
	SIGPROF   = C.SIGPROF
	SIGWINCH  = C.SIGWINCH
	SIGIO     = C.SIGIO
	SIGPWR    = C.SIGPWR
	SIGSYS    = C.SIGSYS

	FPE_INTDIV = C.FPE_INTDIV
	FPE_INTOVF = C.FPE_INTOVF
	FPE_FLTDIV = C.FPE_FLTDIV
	FPE_FLTOVF = C.FPE_FLTOVF
	FPE_FLTUND = C.FPE_FLTUND
	FPE_FLTRES = C.FPE_FLTRES

```

[*路径装饰器依赖项*](dependencies-in-path-operation-decorators.md){.internal-link target=_blank} 一章的思路均适用于全局依赖项， 在本例中，这些依赖项可以用于应用中的所有*路径操作*。

## 为一组路径操作定义依赖项

	// maxBufferSize is the maximum buffer size.
	// Buffers larger than this is not reused.
	maxBufferSize = 96 << 10

	// This is the assumed size of bigger buffers and allocation size.
	biggerBufMin = 32 << 10

	// This is the maximum size of bigger buffers.
	biggerBufMax = maxBufferSize

	// If there is a queue, merge up to this many messages.
	maxMergeMessages = 30

つまり、すでにどこかで使っている通常の依存関係（値を返すもの）を再利用することができ、値は使われなくても依存関係は実行されます:

```Python hl_lines="9 14"
{!../../../docs_src/dependencies/tutorial006.py!}
```

## *path operations*のグループに対する依存関係

	_RFNOWAIT = 1 << 6
	_RFCNAMEG = 1 << 10
	_RFCENVG  = 1 << 11
	_RFCFDG   = 1 << 12
	_RFREND   = 1 << 13
	_RFNOMNT  = 1 << 14
)

// notify
const (
	_NCONT = 0
	_NDFLT = 1
)

type uinptr _Plink

type tos struct {
	prof struct { // Per process profiling
		pp    *_Plink // known to be 0(ptr)
		next  *_Plink // known to be 4(ptr)
		last  *_Plink
		first *_Plink
		pid   uint32
		what  uint32

func TestNoRaceAtomicCrash(t *testing.T) {
	var mutex sync.Mutex
	var nilptr *int32
	panics := 0
	defer func() {
		if x := recover(); x != nil {
			mutex.Lock()
			panics++
			mutex.Unlock()
		} else {
			panic("no panic")
		}
	}()
	atomic.AddInt32(nilptr, 1)
}

func TestNoRaceDeferAtomicStore(t *testing.T) {

	// For bigInt, we use a value that's too big for an int64, but still
	// fits in uint64. go/constant uses a different representation for
	// values larger than int64, but the cmd/asm parser can't parse
	// anything bigger than a uint64.
	bigInt = 0xffffffffffffffff

	stringVal = "test"

	longStringVal = "this_is_a_string_constant_longer_than_seventy_characters_which_used_to_fail_see_issue_50253"
)

var (
	smallIntAsm   int64

## Example

For a simple example, let's consider a file structure similar to the one described in [Bigger Applications](../tutorial/bigger-applications.md){.internal-link target=_blank} and [Testing](../tutorial/testing.md){.internal-link target=_blank}:

```
.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

	fmt.Printf("%s\n", buf)

	// buffer smaller than minimal read size.
	shortBuf := make([]byte, 3)
	if _, err := io.ReadAtLeast(r, shortBuf, 4); err != nil {
		fmt.Println("error:", err)
	}

	// minimal read size bigger than io.Reader stream
	longBuf := make([]byte, 64)
	if _, err := io.ReadAtLeast(r, longBuf, 64); err != nil {
		fmt.Println("error:", err)
	}

	// Output:
	// some io.Reader
	// error: short buffer