MsiSourceListEnumMediaDisksA function (msi.h)

Article
02/09/2023

The MsiSourceListEnumMediaDisks function enumerates the list of disks registered for the media source for a patch or product.

Syntax

UINT MsiSourceListEnumMediaDisksA(
  [in]                LPCSTR            szProductCodeOrPatchCode,
  [in, optional]      LPCSTR            szUserSid,
  [in]                MSIINSTALLCONTEXT dwContext,
  [in]                DWORD             dwOptions,
  [in]                DWORD             dwIndex,
  [out, optional]     LPDWORD           pdwDiskId,
  [out, optional]     LPSTR             szVolumeLabel,
  [in, out, optional] LPDWORD           pcchVolumeLabel,
  [out, optional]     LPSTR             szDiskPrompt,
  [in, out, optional] LPDWORD           pcchDiskPrompt
);

Parameters

[in] szProductCodeOrPatchCode

The ProductCode or patch GUID of the product or patch. Use a null-terminated string. If the string is longer than 39 characters, the function fails and returns ERROR_INVALID_PARAMETER. This parameter cannot be NULL.

[in, optional] szUserSid

A string SID that specifies the user account that contains the product or patch. The SID is not validated or resolved. An incorrect SID can return ERROR_UNKNOWN_PRODUCT or ERROR_UNKNOWN_PATCH. When referencing a machine context, szUserSID must be NULL and dwContext must be MSIINSTALLCONTEXT_MACHINE.

Type of SID	Meaning
NULL	A NULL denotes the currently logged on user. When referencing the current user account, szUserSID can be NULL and dwContext can be MSIINSTALLCONTEXT_USERMANAGED or MSIINSTALLCONTEXT_USERUNMANAGED.
User SID	An enumeration for a specific user in the system. An example of a user SID is "S-1-3-64-2415071341-1358098788-3127455600-2561".
s-1-1-0	The special SID string s-1-1-0 (everyone) specifies enumeration across all users in the system.

Note The special SID string s-1-5-18 (system) cannot be used to enumerate products or patches installed as per-machine. Setting the SID value to s-1-5-18 returns ERROR_INVALID_PARAMETER.

[in] dwContext

This parameter specifies the context of the product or patch instance. This parameter can contain one of the following values.

Type of context	Meaning
MSIINSTALLCONTEXT_USERMANAGED	The product or patch instance exists in the per-user-managed context.
MSIINSTALLCONTEXT_USERUNMANAGED	The product or patch instance exists in the per-user-unmanaged context.
MSIINSTALLCONTEXT_MACHINE	The product or patch instance exists in the per-machine context.

[in] dwOptions

The dwOptions value that specifies the meaning of szProductCodeOrPatchCode.

Flag	Meaning
MSICODE_PRODUCT	szProductCodeOrPatchCode is a product code GUID.
MSICODE_PATCH	szProductCodeOrPatchCode is a patch code GUID.

[in] dwIndex

The index of the source to retrieve. This parameter must be 0 (zero) for the first call to the MsiSourceListEnumMediaDisks function, and then incremented for subsequent calls until the function returns ERROR_NO_MORE_ITEMS.

[out, optional] pdwDiskId

On entry to MsiSourceListEnumMediaDisks this parameter provides a pointer to a DWORD to receive the ID of the disk that is being enumerated. This parameter is optional.

[out, optional] szVolumeLabel

An output buffer that receives the volume label of the disk that is being enumerated. This buffer should be large enough to contain the information. If the buffer is too small, the function returns ERROR_MORE_DATA and sets *pcchVolumeLabel to the number of TCHAR in the value, not including the terminating NULL character.

If szVolumeLabel and pcchVolumeLabel are both set to NULL, the function returns ERROR_SUCCESS if the value exists, without retrieving the value.

[in, out, optional] pcchVolumeLabel

A pointer to a variable that specifies the number of TCHAR in the szVolumeLabel buffer. When the function returns, this parameter is the number of TCHAR in the received value, not including the terminating null character.

This parameter can be set to NULL only if szVolumeLabel is also NULL, otherwise the function returns ERROR_INVALID_PARAMETER.

[out, optional] szDiskPrompt

An output buffer that receives the disk prompt of the disk that is being enumerated. This buffer should be large enough to contain the information. If the buffer is too small, the function returns ERROR_MORE_DATA and sets *pcchDiskPrompt to the number of TCHAR in the value, not including the terminating NULL character.

If the szDiskPrompt is set to NULL and pcchDiskPrompt is set to a valid pointer, the function returns ERROR_SUCCESS and sets *pcchDiskPrompt to the number of TCHAR in the value, not including the terminating NULL character. The function can then be called again to retrieve the value, with szDiskPrompt buffer large enough to contain *pcchDiskPrompt + 1 characters.

If szDiskPrompt and pcchDiskPrompt are both set to NULL, the function returns ERROR_SUCCESS if the value exists, without retrieving the value.

[in, out, optional] pcchDiskPrompt

A pointer to a variable that specifies the number of TCHAR in the szDiskPrompt buffer. When the function returns, this parameter is set to the size of the requested value whether or not the function copies the value into the specified buffer. The size is returned as the number of TCHAR in the requested value, not including the terminating null character.

This parameter can be set to NULL only if szDiskPrompt is also NULL, otherwise the function returns ERROR_INVALID_PARAMETER.

Return value

The MsiSourceListEnumMediaDisks function returns the following values.

Value	Meaning
ERROR_ACCESS_DENIED	The user does not have the ability to read the specified media source or the specified product or patch. This does not indicate whether a media source, product, or patch is found.
ERROR_BAD_CONFIGURATION	The configuration data is corrupt.
ERROR_INVALID_PARAMETER	An invalid parameter is passed to the function.
ERROR_NO_MORE_ITEMS	There are no more disks registered for this product or patch.
ERROR_SUCCESS	The value is enumerated successfully.
ERROR_UNKNOWN_PATCH	The patch is not found.
ERROR_UNKNOWN_PRODUCT	The product is not found.
ERROR_MORE_DATA	The buffer that is provided is too small to contain the requested information.
ERROR_FUNCTION_FAILED	Unexpected internal failure.

Remarks

When making multiple calls to MsiSourceListEnumMediaDisks to enumerate all the sources for a single product instance, each call must be made from the same thread.

An administrator can enumerate per-user unmanaged and managed installations for themselves, per-machine installations, and per-user managed installations for any user. An administrator cannot enumerate per-user unmanaged installations for other users. Non-administrators can only enumerate their own per-user unmanaged and managed installations and per-machine installations.

Note

The msi.h header defines MsiSourceListEnumMediaDisks as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement	Value
Minimum supported client	Windows Installer 5.0 on Windows Server 2012, Windows 8, Windows Server 2008 R2 or Windows 7. Windows Installer 4.0 or Windows Installer 4.5 on Windows Server 2008 or Windows Vista. Windows Installer 3.0 or later on Windows Server 2003 or Windows XP. See the Windows Installer Run-Time Requirements for information about the minimum Windows service pack that is required by a Windows Installer version.
Target Platform	Windows
Header	msi.h
Library	Msi.lib
DLL	Msi.dll