8. CreateToolhelp32Snapshot

선언:

C#

[DllImport("kernel32")]
public static extern IntPtr CreateToolhelp32Snapshot(Int32 dwFlags, Int32 th32ProcessID);

VB.NET

<DllImport("kernel32")> _
Public Shared Function CreateToolhelp32Snapshot(dwFlags As Int32, th32ProcessID As Int32) As IntPtr
End Function

사용 예제:

C#

using System;
using System.Runtime.InteropServices;
using System.Collections.Generic;

namespace ApiReference {
    public class ApiReference {
        [DllImport("kernel32")]
        public static extern IntPtr CreateToolhelp32Snapshot(Int32 dwFlags, Int32 th32ProcessID);
        [DllImport("kernel32")]
        public static extern void CloseHandle(IntPtr hObject);
        [DllImport("kernel32")]
        public static extern Int32 Process32First(IntPtr hSnapshot, ref PROCESSENTRY32 pe32);
        [DllImport("kernel32")]
        public static extern Int32 Process32Next(IntPtr hSnapshot, ref PROCESSENTRY32 pe32);
        
        public const Int32 MAX_PATH = 260;
        public const Int32 TH32CS_SNAPPROCESS = 2;
        
        [StructLayout(LayoutKind.Sequential)]
        public struct PROCESSENTRY32 {
            public Int32 dwSize;
            public Int32 cntUsage;
            public Int32 th32ProcessID;
            public IntPtr th32DefaultHeapID;
            public Int32 th32ModuleID;
            public Int32 cntThreads;
            public Int32 th32ParentProcessID;
            public Int32 pcPriClassBase;
            public Int32 dwFlags;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH)]
            public String szExeFile;

            public static Int32 Size {
                get { return Marshal.SizeOf(typeof(PROCESSENTRY32)); }
            }
        }
        
        public static void Main(String[] args) {
            Console.WriteLine("프로세스 목록을 가져오는 중입니다!");
            List<PROCESSENTRY32> processes = EnumProcesses();
            
            if ( processes != null ) {
                foreach ( PROCESSENTRY32 pe32 in processes ) {
                    Console.WriteLine("{0,-5}\t{1,-5}\t{2}", pe32.th32ProcessID, pe32.th32ParentProcessID, pe32.szExeFile);
                }
            } else
                Console.WriteLine("목록 정보 가져오기 실패!");
            
            Console.ReadKey(true);
        }
        
        public static List<PROCESSENTRY32> EnumProcesses() {
            IntPtr hSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
            if ( hSnapshot == IntPtr.Zero )
                return null;

            PROCESSENTRY32 pe32 = new PROCESSENTRY32();
            pe32.dwSize = PROCESSENTRY32.Size;
            if ( Process32First(hSnapshot, ref pe32) == 0 ) {
                CloseHandle(hSnapshot);
                return null;
            }

            List<PROCESSENTRY32> lstProcesses = new List<PROCESSENTRY32>();
            do {
                lstProcesses.Add(pe32);
            } while ( Process32Next(hSnapshot, ref pe32) != 0 );

            CloseHandle(hSnapshot);
            return lstProcesses;
        }
    }
}

VB.NET

Imports System
Imports System.Runtime.InteropServices
Imports System.Collections.Generic

Namespace ApiReference
    Public Class ApiReference
        <DllImport("kernel32")> _
        Public Shared Function CreateToolhelp32Snapshot(dwFlags As Int32, th32ProcessID As Int32) As IntPtr
        End Function
        <DllImport("kernel32")> _
        Public Shared Sub CloseHandle(hObject As IntPtr)
        End Sub
        <DllImport("kernel32")> _
        Public Shared Function Process32First(hSnapshot As IntPtr, ByRef pe32 As PROCESSENTRY32) As Int32
        End Function
        <DllImport("kernel32")> _
        Public Shared Function Process32Next(hSnapshot As IntPtr, ByRef pe32 As PROCESSENTRY32) As Int32
        End Function

        Public Const MAX_PATH As Int32 = 260
        Public Const TH32CS_SNAPPROCESS As Int32 = 2

        <StructLayout(LayoutKind.Sequential)> _
        Public Structure PROCESSENTRY32
            Public dwSize As Int32
            Public cntUsage As Int32
            Public th32ProcessID As Int32
            Public th32DefaultHeapID As IntPtr
            Public th32ModuleID As Int32
            Public cntThreads As Int32
            Public th32ParentProcessID As Int32
            Public pcPriClassBase As Int32
            Public dwFlags As Int32
            <MarshalAs(UnmanagedType.ByValTStr, SizeConst := MAX_PATH)> _
            Public szExeFile As [String]

            Public Shared ReadOnly Property Size() As Int32
                Get
                    Return Marshal.SizeOf(GetType(PROCESSENTRY32))
                End Get
            End Property
        End Structure

        Public Shared Sub Main(args As [String]())
            Console.WriteLine("프로세스 목록을 가져오는 중입니다!")
            Dim processes As List(Of PROCESSENTRY32) = EnumProcesses()

            If processes IsNot Nothing Then
                For Each pe32 As PROCESSENTRY32 In processes
                    Console.WriteLine("{0,-5}" & vbTab & "{1,-5}" & vbTab & "{2}", pe32.th32ProcessID, pe32.th32ParentProcessID, pe32.szExeFile)
                Next
            Else
                Console.WriteLine("목록 정보 가져오기 실패!")
            End If

            Console.ReadKey(True)
        End Sub

        Public Shared Function EnumProcesses() As List(Of PROCESSENTRY32)
            Dim hSnapshot As IntPtr = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0)
            If hSnapshot = IntPtr.Zero Then
                Return Nothing
            End If

            Dim pe32 As New PROCESSENTRY32()
            pe32.dwSize = PROCESSENTRY32.Size
            If Process32First(hSnapshot, pe32) = 0 Then
                CloseHandle(hSnapshot)
                Return Nothing
            End If

            Dim lstProcesses As New List(Of PROCESSENTRY32)()
            Do
                lstProcesses.Add(pe32)
            Loop While Process32Next(hSnapshot, pe32) <> 0

            CloseHandle(hSnapshot)
            Return lstProcesses
        End Function
    End Class
End Namespace

예제 실행 결과:

매개 변수 설명:

dwFlags - 가져올 스냅샷 정보를 입력합니다.

th32ProcessID - 스냅샷을 가져올 프로세스의 식별자를 입력합니다.

API 설명:

지정된 프로세스 혹은 시스템의 지정된 정보의 스냅샷을 생성합니다.

참고:

CreateToolhelp32Snapshot (MSDN)

비고:

TH32CS_SNAPHEAPLIST, TH32CS_SNAPMODULE, TH32CS_SNAPMODULE32, TH32CS_SNAPALL 이 4개의

옵션을 입력한 경우에만 th32ProcessID 매개 변수가 유효합니다. 그 외의 경우엔 th32ProcessID 매개 변수에

대개 0을 입력합니다.

또한, TH32CS_SNAPMODULE32 옵션의 경우 64비트 윈도우에서만 사용이 가능합니다.