Item

Description

Structure

STARTUPINFO.

Info

Is used with the CreateProcess(), CreateProcessAsUser(), and CreateProcessWithLogonW() functions to specify the window station, desktop, standard handles, and appearance of the main window for the new process.

Definition

typedef struct _STARTUPINFO {

  DWORD cb;

  LPTSTR lpReserved;

  LPTSTR lpDesktop;

  LPTSTR lpTitle;

  DWORD dwX;

  DWORD dwY;

  DWORD dwXSize;

  DWORD dwYSize;

  DWORD dwXCountChars;

  DWORD dwYCountChars;

  DWORD dwFillAttribute;

  DWORD dwFlags;

  WORD wShowWindow;

  WORD cbReserved2;

  LPBYTE lpReserved2;

  HANDLE hStdInput;

  HANDLE hStdOutput;

  HANDLE hStdError;

} STARTUPINFO, *LPSTARTUPINFO;

Members

See below.

Header file

<windows.h>

Remark

Declared as Unicode and ANSI structures. For graphical user interface (GUI) processes, this information affects the first window created by the CreateWindow() function and shown by the ShowWindow() function. For console processes, this information affects the console window if a new console is created for the process. A process can use the GetStartupInfo() function to retrieve the STARTUPINFO structure specified when the process was created. If a GUI process is being started and neither STARTF_FORCEONFEEDBACK or STARTF_FORCEOFFFEEDBACK is specified, the process feedback cursor is used. A GUI process is one whose subsystem is specified as "windows".

Table 1.

Item

Description

Structure

PROCESS_INFORMATION.

Info

Is filled in by either the CreateProcess(), CreateProcessAsUser(), CreateProcessWithLogonW(), or CreateProcessWithTokenW() function with information about the newly created process and its primary thread.

Definition

typedef struct _PROCESS_INFORMATION {

  HANDLE hProcess;

  HANDLE hThread;

  DWORD dwProcessId;

  DWORD dwThreadId;

} PROCESS_INFORMATION;

Members

hProcess - Handle to the newly created process. The handle is used to specify the process in all functions that perform operations on the process object.

hThread - Handle to the primary thread of the newly created process. The handle is used to specify the thread in all functions that perform operations on the thread object.

dwProcessId - Value that can be used to identify a process. The value is valid from the time the process is created until the time the process is terminated.

dwThreadId - Value that can be used to identify a thread. The value is valid from the time the thread is created until the time the thread is terminated.

Header file

<windows.h>

Remark

If the function succeeds, be sure to call the CloseHandle() function to close the hProcess and hThread handles when you are finished with them. Otherwise, when the child process exits, the system cannot clean up these handles because the parent process did not close them. However, the system will close these handles when the parent process terminates, so they would be cleaned up at this point.

Table 3.

Item

Description

Structure

SECURITY_ATTRIBUTES.

Info

Contains the security descriptor for an object and specifies whether the handle retrieved by specifying this structure is inheritable. This structure provides security settings for objects created by various functions, such as CreateFile(), CreatePipe(), CreateProcess(), RegCreateKeyEx(), or RegSaveKeyEx().

Definition

typedef struct _SECURITY_ATTRIBUTES {

  DWORD nLength;

  LPVOID lpSecurityDescriptor;

  BOOL bInheritHandle;

} SECURITY_ATTRIBUTES, *PSECURITY_ATTRIBUTES;

Members

nLength - Specifies the size, in bytes, of this structure. Set this value to the size of the SECURITY_ATTRIBUTES structure.

lpSecurityDescriptor - Pointer to a security descriptor for the object that controls the sharing of it. If NULL is specified for this member, the object is assigned the default security descriptor of the calling process. This is not the same as granting access to everyone by assigning a NULL DACL. The default security descriptor is based on the default DACL of the access token belonging to the calling process. By default, the default DACL in the access token of a process allows access only to the user represented by the access token. If other users must access the object, you can either create a security descriptor with the appropriate access, or add ACEs to the DACL that grants access to a group of users. For Windows 95/98/Me: The lpSecurityDescriptor member of this structure is ignored.

bInheritHandle - Specifies whether the returned handle is inherited when a new process is created. If this member is TRUE, the new process inherits the handle.

Header file

<windows.h>

Remark

-

Table 4.

Item

Description

Structure

GENERIC_MAPPING.

Info

Defines the mapping of generic access rights to specific and standard access rights for an object. When a client application requests generic access to an object, that request is mapped to the access rights defined in this structure.

Definition

typedef struct _GENERIC_MAPPING {

  ACCESS_MASK GenericRead;

  ACCESS_MASK GenericWrite;

  ACCESS_MASK GenericExecute;

  ACCESS_MASK GenericAll;

} GENERIC_MAPPING;

Members

GenericRead - Specifies an access mask defining read access to an object.

GenericWrite - Specifies an access mask defining write access to an object.

GenericExecute - Specifies an access mask defining execute access to an object.

GenericAll - Specifies an access mask defining all possible types of access to an object.

Header file

<windows.h>

Remark

-

Table 5.

Item

Description

Structure

PRIVILEGE_SET.

Info

Specifies a set of privileges. It is also used to indicate which, if any, privileges are held by a user or group requesting access to an object.

Definition

typedef struct _PRIVILEGE_SET {

  DWORD PrivilegeCount;

  DWORD Control;

  LUID_AND_ATTRIBUTES Privilege[ANYSIZE_ARRAY];

} PRIVILEGE_SET,  *PPRIVILEGE_SET;

Members

PrivilegeCount - Specifies the number of privileges in the privilege set.

Control - Specifies a control flag related to the privileges. The PRIVILEGE_SET_ALL_NECESSARY control flag is currently defined. It indicates that all of the specified privileges must be held by the process requesting access. If this flag is not set, the presence of any privileges in the user's access token grants the access.

Privilege - Specifies an array of LUID_AND_ATTRIBUTES structures describing the set's privileges. The following attributes are defined for privileges:

1. SE_PRIVILEGE_ENABLED_BY_DEFAULT - The privilege is enabled by default.

2. SE_PRIVILEGE_ENABLED - The privilege is enabled.

3. SE_PRIVILEGE_USED_FOR_ACCESS - The privilege was used to gain access to an object or service. This flag is used to identify the relevant privileges in a set passed by a client application that may contain unnecessary privileges.

Header file

<windows.h>

Remark

A privilege is used to control access to an object or service more strictly than is typical with discretionary access control. A system manager uses privileges to control which users are able to manipulate system resources. An application uses privileges when it changes a system-wide resource, such as when it changes the system time or shuts down the system.

Table 6.

Item

Description

Structure

LUID_AND_ATTRIBUTES.

Info

Represents a locally unique identifier (LUID) and its attributes.

Definition

typedef struct _LUID_AND_ATTRIBUTES {

  LUID Luid;

  DWORD Attributes;

} LUID_AND_ATTRIBUTES, *PLUID_AND_ATTRIBUTES;

Members

Luid - Specifies an LUID value.

Attributes - Specifies attributes of the LUID. This value contains up to 32 one-bit flags. Its meaning is dependent on the definition and use of the LUID.

Header file

<windows.h>

Remark

An LUID_AND_ATTRIBUTES structure can represent an LUID whose attributes change frequently, such as when the LUID is used to represent privileges in the PRIVILEGE_SET structure. Privileges are represented by LUIDs and have attributes indicating whether they are currently enabled or disabled.

Table 7.

Item

Description

Structure

LUID.

Info

Is a 64-bit value guaranteed to be unique only on the system on which it was generated. The uniqueness of a locally unique identifier (LUID) is guaranteed only until the system is restarted. An LUID is not for direct manipulation. Applications are to use functions and structures to manipulate LUID values.

Definition

typedef struct _LUID {

  DWORD LowPart;

  LONG HighPart;

} LUID, *PLUID;

Members

LowPart - Low order bits.

HighPart - High order bits.

Header file

<windows.h>

Remark

-

Table 8.

Item

Description

Structure

SECURITY_DESCRIPTOR.

Info

Contains the security information associated with an object. Applications use this structure to set and query an object's security status. Because the internal format of a security descriptor can vary, applications are not to modify the SECURITY_DESCRIPTOR structure directly.

Definition

typedef struct SECURITY_DESCRIPTOR {

  ...

} SECURITY_DESCRIPTOR, *PISECURITY_DESCRIPTOR, PSECURITY_DESCRIPTOR;

Members

User defined.

Header file

<windows.h>

Remark

A security descriptor includes information that specifies the following components of an object's security:

1. An owner (SID).

2. A primary group (SID).

3. A discretionary ACL.

4. A system ACL.

5. Qualifiers for the preceding items.

Several functions that use the SECURITY_DESCRIPTOR structure require that this structure be on a valid pointer boundary in memory. These boundaries vary depending on the type of processor used. Memory allocation functions, such as malloc and LocalAlloc(), return properly aligned pointers.

Table 9.

Item

Description

Structure

THREADENTRY32.

Info

Describes an entry from a list that enumerates the threads executing in the system when a snapshot was taken.

Definition

typedef struct tagTHREADENTRY32 {

  DWORD dwSize;

  DWORD cntUsage;

  DWORD th32ThreadID;

  DWORD th32OwnerProcessID;

  LONG tpBasePri;

  LONG tpDeltaPri;

  DWORD dwFlags;

} THREADENTRY32, *PTHREADENTRY32;

Members

See below.

Header file

<tlhelp32.h>

Remark

-

Table 10.

Item

Description

Structure

PROCESSENTRY32.

Info

Describes an entry from a list that enumerates the processes residing in the system address space when a snapshot was taken.

Definition

typedef struct tagPROCESSENTRY32 {

  DWORD dwSize;

  DWORD cntUsage;

  DWORD th32ProcessID;

  ULONG_PTR th32DefaultHeapID;

  DWORD th32ModuleID;

  DWORD cntThreads;

  DWORD th32ParentProcessID;

  LONG pcPriClassBase;

  DWORD dwFlags;

  TCHAR szExeFile[MAX_PATH];

} PROCESSENTRY32, *PPROCESSENTRY32;

Members

dwSize - Size of the structure, in bytes. Before calling the Process32First() function, set this member to sizeof(PROCESSENTRY32). If you do not initialize dwSize, Process32First() fails.

cntUsage - This member is no longer used and is always set to zero.

th32ProcessID - Process identifier.

th32DefaultHeapID - This member is no longer used and is always set to zero.

th32ModuleID - This member is no longer used and is always set to zero.

cntThreads - Number of execution threads started by the process.

th32ParentProcessID - Process identifier of the process that created this process (its parent process).

pcPriClassBase - Base priority of any threads created by this process.

dwFlags - This member is no longer used, and is always set to zero.

szExeFile - Pointer to a null-terminated string that specifies the name of the executable file for the process.

Header file

<tlhelp32.h>

Remark

-

Item

Description

Structure

MODULEENTRY32.

Info

Describes an entry from a list that enumerates the modules used by a specified process.

Definition

typedef struct tagMODULEENTRY32 {

  DWORD dwSize;

  DWORD th32ModuleID;

  DWORD th32ProcessID;

  DWORD GlblcntUsage;

  DWORD ProccntUsage;

  BYTE* modBaseAddr;

  DWORD modBaseSize;

  HMODULE hModule;

  TCHAR szModule[MAX_MODULE_NAME32 + 1];

  TCHAR szExePath[MAX_PATH];

} MODULEENTRY32, *PMODULEENTRY32;

Members

dwSize - Size of the structure, in bytes. Before calling the Module32First() function, set this member to sizeof(MODULEENTRY32). If you do not initialize dwSize, Module32First() fails.

th32ModuleID - This member is no longer used, and is always set to one.

th32ProcessID - Win32 process identifier of the process whose modules are to be examined.

GlblcntUsage - The load count of the module, which is not generally meaningful, and usually equal to 0xFFFF.

ProccntUsage - Same as GlblcntUsage: the load count of the module, which is not generally meaningful, and usually equal to 0xFFFF.

modBaseAddr - Base address of the module in the context of the owning process.

modBaseSize - Size of the module, in bytes.

hModule - Handle to the module in the context of the owning process.

szModule - Pointer to a null-terminated string that specifies the module name.

szExePath - Pointer to a null-terminated string that specifies the module path.

Header file

<tlhelp32.h>

Remark

The modBaseAddr and hModule members are valid only in the context of the process specified by th32ProcessID.

Table 13.

Item

Description

Structure

OVERLAPPED.

Info

Contains information used in asynchronous input and output (I/O).

Definition

typedef struct _OVERLAPPED {

  ULONG_PTR Internal;

  ULONG_PTR InternalHigh;

  DWORD Offset;

  DWORD OffsetHigh;

  HANDLE hEvent;

} OVERLAPPED;

Members

Internal - Reserved for operating system use. This member, which specifies a system-dependent status, is valid when the GetOverlappedResult() function returns without setting the extended error information to ERROR_IO_PENDING.

InternalHigh - Reserved for operating system use. This member, which specifies the length of the data transferred, is valid when the GetOverlappedResult() function returns TRUE.

Offset - File position at which to start the transfer. The file position is a byte offset from the start of the file. The calling process sets this member before calling the ReadFile() or WriteFile() function. sThis member is ignored when reading from or writing to named pipes and during serial communication and should be zero.

OffsetHigh - High-order word of the byte offset at which to start the transfer. This member is ignored when reading from or writing to named pipes and communications devices and should be zero.

hEvent - Handle to an event set to the signaled state when the operation has been completed. The calling process must set this member either to zero or a valid event handle before calling any overlapped functions.

To create an event object, use the CreateEvent() function. Some of the functions used with overlapped I/O (such as GetOverlappedResult()) may wait on this handle. Therefore, if you use an automatic reset event, your application can hang if such a function is already waiting on the handle when you begin to wait on it. Functions such as WriteFile() set the event to the non-signaled state before they begin an I/O operation.

Header file

<windows.h>

Remark

This structure should always be initialized to zero before it is used in a function call. If it is not, the function may fail and return ERROR_INVALID_PARAMETER. You can use the HasOverlappedIoCompleted() macro to determine whether an asynchronous I/O operation has completed. You can use the CancelIo function to cancel an asynchronous I/O operation.

Table 14.

Item

Description

Structure

SLIST_ENTRY.

Info

Represents an item in a singly linked list.

Definition

typedef struct _SLIST_ENTRY {

  struct _SLIST_ENTRY* Next;

} SLIST_ENTRY, *PSLIST_ENTRY;

Members

Next - Pointer to an SLIST_ENTRY structure that represents the next item in a singly linked list.

Header file

<windows.h>

Remark

-

Table 15.

Item

Description

Structure

MSG.

Info

Contains message information from a thread's message queue.

Definition

typedef struct {

    HWND hwnd;

    UINT message;

    WPARAM wParam;

    LPARAM lParam;

    DWORD time;

    POINT pt;

} MSG, *PMSG;

Members

hwnd - Handle to the window whose window procedure receives the message.

message - Specifies the message identifier. Applications can only use the low word; the high word is reserved by the system.

wParam - Specifies additional information about the message. The exact meaning depends on the value of the message member.

lParam - Specifies additional information about the message. The exact meaning depends on the value of the message member.

time - Specifies the time at which the message was posted.

pt - Specifies the cursor position, in screen coordinates, when the message was posted.

Header file

<windows.h>

Remark

-

Table 16.