github.com/mdempsky/go@v0.0.0-20151201204031-5dd372bd1e70/src/os/exec.go (about)

     1  // Copyright 2009 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package os
     6  
     7  import (
     8  	"runtime"
     9  	"sync/atomic"
    10  	"syscall"
    11  )
    12  
    13  // Process stores the information about a process created by StartProcess.
    14  type Process struct {
    15  	Pid    int
    16  	handle uintptr // handle is accessed atomically on Windows
    17  	isdone uint32  // process has been successfully waited on, non zero if true
    18  }
    19  
    20  func newProcess(pid int, handle uintptr) *Process {
    21  	p := &Process{Pid: pid, handle: handle}
    22  	runtime.SetFinalizer(p, (*Process).Release)
    23  	return p
    24  }
    25  
    26  func (p *Process) setDone() {
    27  	atomic.StoreUint32(&p.isdone, 1)
    28  }
    29  
    30  func (p *Process) done() bool {
    31  	return atomic.LoadUint32(&p.isdone) > 0
    32  }
    33  
    34  // ProcAttr holds the attributes that will be applied to a new process
    35  // started by StartProcess.
    36  type ProcAttr struct {
    37  	// If Dir is non-empty, the child changes into the directory before
    38  	// creating the process.
    39  	Dir string
    40  	// If Env is non-nil, it gives the environment variables for the
    41  	// new process in the form returned by Environ.
    42  	// If it is nil, the result of Environ will be used.
    43  	Env []string
    44  	// Files specifies the open files inherited by the new process.  The
    45  	// first three entries correspond to standard input, standard output, and
    46  	// standard error.  An implementation may support additional entries,
    47  	// depending on the underlying operating system.  A nil entry corresponds
    48  	// to that file being closed when the process starts.
    49  	Files []*File
    50  
    51  	// Operating system-specific process creation attributes.
    52  	// Note that setting this field means that your program
    53  	// may not execute properly or even compile on some
    54  	// operating systems.
    55  	Sys *syscall.SysProcAttr
    56  }
    57  
    58  // A Signal represents an operating system signal.
    59  // The usual underlying implementation is operating system-dependent:
    60  // on Unix it is syscall.Signal.
    61  type Signal interface {
    62  	String() string
    63  	Signal() // to distinguish from other Stringers
    64  }
    65  
    66  // Getpid returns the process id of the caller.
    67  func Getpid() int { return syscall.Getpid() }
    68  
    69  // Getppid returns the process id of the caller's parent.
    70  func Getppid() int { return syscall.Getppid() }