VARSTRING

The VARSTRING structure is used for returning variably sized strings. It is used both by the line device class and the phone device class.

typedef struct varstring_tag {
  DWORD  dwTotalSize;
  DWORD  dwNeededSize;
  DWORD  dwUsedSize;
  DWORD  dwStringFormat;
  DWORD  dwStringSize;
  DWORD  dwStringOffset;
} VARSTRING, FAR *LPVARSTRING; 

Members

dwTotalSize

The total size, in bytes, allocated to this data structure.

dwNeededSize

The size, in bytes, for this data structure that is needed to hold all the returned information.

dwUsedSize

The size, in bytes, of the portion of this data structure that contains useful information.

dwStringFormat

The format of the string. This member uses one of the STRINGFORMAT_ Constants.

dwStringSize

dwStringOffset

The size, in bytes, of the variably sized device field containing the string information, and the offset, in bytes, from the beginning of this data structure.

Remarks

No extensibility.

If a string cannot be returned in a variable structure, the dwStringSize and dwStringOffset members are set in one of the following ways:

• dwStringSize and dwStringOffset members are both set to zero.
• dwStringOffset is nonzero and dwStringSize is zero.
• dwStringOffset is nonzero, dwStringSize is 1, and the byte at the given offset is zero.

Requirements

  Windows NT/2000: Requires Windows NT 4.0 SP3 or later.
  Windows 95/98: Requires Windows 95 or later.
  Version: Requires TAPI 1.4 or later.
  Header: Declared in Tapi.h.