acmFormatTagEnum

  • Article

The acmFormatTagEnum function enumerates waveform-audio format tags available from an ACM driver. This function continues enumerating until there are no more suitable format tags or the callback function returns FALSE.

MMRESULT acmFormatTagEnum(
  HACMDRIVER            had,       
  LPACMFORMATTAGDETAILS paftd,     
  ACMFORMATTAGENUMCB    fnCallback,
  DWORD_PTR             dwInstance,
  DWORD                 fdwEnum    
);

Parameters

had

Handle to the ACM driver to query for waveform-audio format tag details. If this parameter is NULL, the ACM uses the details from the first suitable ACM driver.

paftd

Pointer to the ACMFORMATTAGDETAILS structure that is to receive the format tag details passed to the function specified in fnCallback. This structure must have the cbStruct member of the ACMFORMATTAGDETAILS structure initialized.

fnCallback

Procedure instance address of the application-defined callback function.

dwInstance

A 64-bit (DWORD_PTR) or 32-bit (DWORD) application-defined value that is passed to the callback function along with ACM format tag details.

fdwEnum

Reserved; must be zero.

Return Values

Returns zero if successful or an error otherwise. Possible error values include the following.

Value Description
MMSYSERR_INVALFLAG At least one flag is invalid.
MMSYSERR_INVALHANDLE The specified handle is invalid.
MMSYSERR_INVALPARAM At least one parameter is invalid.

Remarks

This function will return MMSYSERR_NOERROR (zero) if no suitable ACM drivers are installed. Moreover, the callback function will not be called.

Requirements

**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Msacm.h.
**  Library:** Use Msacm32.lib.
**  Unicode:** Implemented as Unicode and ANSI versions on Windows NT/2000/XP.

See Also

Audio Compression Manager, Audio Compression Functions, ACMFORMATTAGDETAILS