Checks for specified operating systems and operating system features.

Syntax

BOOL IsOS(      
    DWORD dwOS
);

Parameters

dwOS

[in] A value that specifies which operating system or operating system feature to check for. One of the following values (you cannot combine values).

Name	Value	Description
OS_WINDOWS	0	The program is running on one of the following versions of Microsoft Windows: Windows 95 Windows 98 Windows Me Equivalent to VER_PLATFORM_WIN32_WINDOWS. Note that none of those systems are supported at this time. OS_WINDOWS returns FALSE on all supported systems.
OS_NT	1	Always returns TRUE.
OS_WIN95ORGREATER	2	Always returns FALSE.
OS_NT4ORGREATER	3	Always returns FALSE.
OS_WIN98ORGREATER	5	Always returns FALSE.
OS_WIN98_GOLD	6	Always returns FALSE.
OS_WIN2000ORGREATER	7	The program is running on Windows 2000 or one of its successors.
OS_WIN2000PRO	8	Do not use; use OS_PROFESSIONAL.
OS_WIN2000SERVER	9	Do not use; use OS_SERVER.
OS_WIN2000ADVSERVER	10	Do not use; use OS_ADVSERVER.
OS_WIN2000DATACENTER	11	Do not use; use OS_DATACENTER.
OS_WIN2000TERMINAL	12	The program is running on Windows 2000 Terminal Server in either Remote Administration mode or Application Server mode, or Windows Server 2003 (or one of its successors) in Terminal Server mode or Remote Desktop for Administration mode. Consider using a more specific value such as OS_TERMINALSERVER, OS_TERMINALREMOTEADMIN, or OS_PERSONALTERMINALSERVER.
OS_EMBEDDED	13	The program is running on Windows Embedded, any version. Equivalent to VER_SUITE_EMBEDDEDNT.
OS_TERMINALCLIENT	14	The program is running as a Terminal Server client. Equivalent to GetSystemMetrics(SM_REMOTESESSION).
OS_TERMINALREMOTEADMIN	15	The program is running on Windows 2000 Terminal Server in the Remote Administration mode or Windows Server 2003 (or one of its successors) in the Remote Desktop for Administration mode (these are the default installation modes). This is equivalent to VER_SUITE_TERMINAL && ER_SUITE_SINGLEUSERTS.
OS_WIN95_GOLD	16	Always returns FALSE.
OS_MEORGREATER	17	Always returns FALSE.
OS_XPORGREATER	18	Always returns FALSE.
OS_HOME	19	Always returns FALSE.
OS_PROFESSIONAL	20	The program is running on Microsoft Windows NT Workstation or Windows 2000 (or one of its successors) Professional. Equivalent to VER_PLATFORM_WIN32_NT && VER_NT_WORKSTATION.
OS_DATACENTER	21	The program is running on Windows Datacenter Server or Windows Server Datacenter Edition, any version. Equivalent to (VER_NT_SERVER || VER_NT_DOMAIN_CONTROLLER) && VER_SUITE_DATACENTER.
OS_ADVSERVER	22	The program is running on Windows Advanced Server or Windows Server Enterprise Edition, any version. Equivalent to (VER_NT_SERVER || VER_NT_DOMAIN_CONTROLLER) && VER_SUITE_ENTERPRISE && !VER_SUITE_DATACENTER.
OS_SERVER	23	The program is running on Windows Server (Standard) or Windows Server Standard Edition, any version. This value will not return true for VER_SUITE_DATACENTER, VER_SUITE_ENTERPRISE, VER_SUITE_SMALLBUSINESS, or VER_SUITE_SMALLBUSINESS_RESTRICTED.
OS_TERMINALSERVER	24	The program is running on Windows 2000 Terminal Server in Application Server mode, or on Windows Server 2003 (or one of its successors) in Terminal Server mode. This is equivalent to VER_SUITE_TERMINAL && VER_SUITE_SINGLEUSERTS.
OS_PERSONALTERMINALSERVER	25	The program is running on Windows XP (or one of its successors), Home Edition or Professional. This is equivalent to ER_SUITE_SINGLEUSERTS && !VER_SUITE_TERMINAL.
OS_FASTUSERSWITCHING	26	Fast user switching is enabled.
OS_WELCOMELOGONUI	27	Always returns FALSE.
OS_DOMAINMEMBER	28	The computer is joined to a domain.
OS_ANYSERVER	29	The program is running on any Windows Server product. Equivalent to VER_NT_SERVER || VER_NT_DOMAIN_CONTROLLER.
OS_WOW6432	30	The program is a 32-bit program running on Microsoft Win64.
OS_WEBSERVER	31	Always returns FALSE.
OS_SMALLBUSINESSSERVER	32	The program is running on Microsoft Small Business Server with restrictive client license in force. Equivalent to VER_SUITE_SMALLBUSINESS_RESTRICTED.
OS_TABLETPC	33	The program is running on Windows XP Tablet PC Edition, or one of its successors.
OS_SERVERADMINUI	34	The user should be presented with administrator user interface (UI). It is possible to have server administrative UI on a non-server machine. This value informs the application that an administrator's profile has roamed to a non-server, and UI should be appropriate to an administrator. Otherwise, the user is shown a mix of administrator and nonadministrator settings.
OS_MEDIACENTER	35	The program is running on Windows XP Media Center Edition, or one of its successors. Equivalent to GetSystemMetrics(SM_MEDIACENTER).
OS_APPLIANCE	36	The program is running on Windows Appliance Server.

Return Value

Returns a nonzero value if the specified operating system or operating system feature is detected, otherwise FALSE.

Remarks

Values are not provided for Windows Vista and Windows 7. To determine whether either of those operating systems are present, use VerifyVersionInfo.

In Windows versions earlier than Windows Vista, IsOS was not exported by name or declared in a public header file. To use it in those cases, you must use GetProcAddress and request ordinal 437 from Shlwapi.dll to obtain a function pointer. Under Windows Vista, IsOS is included in Shlwapi.h and this is not necessary.

When referring to server products, "Windows Server" refers only to the Standard Edition server. If all server products are covered by a particular flag, it is called out explicitly in the table.

Function Information

Minimum DLL Version	shlwapi.dll version 5.0 or later
Custom Implementation	No
Header	shlwapi.h
Import library	None
Minimum operating systems	Windows 2000, Windows 2000 Server, Windows Server 2003, Windows XP

See Also

GetSystemMetrics, GetVersionEx, VerifyVersionInfo