VARSTRING

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

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 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 the following STRINGFORMAT_ constants:

STRINGFORMAT_ASCII

ASCII string format using one byte per character. The actual string is a NULL-terminated ASCII string with the terminating NULL accounted for in the string size. If dwStringFormat is STRINGFORMAT_ASCII, the actual string is a NULL-terminated ASCII string with the terminating NULL accounted for in the string size.

STRINGFORMAT_DBCS

DBCS string format using one or two bytes per character.

STRINGFORMAT_UNICODE

Unicode string format using two bytes per character.

STRINGFORMAT_BINARY

Array of unsigned characters. It can be used for numeric values.

dwStringSize

dwStringOffset

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

Remarks

Not extensible.

If the dwStringSize and dwStringOffset members are set in any one of the following ways, the structure contain no string or an empty string:

• Both the dwStringSize and dwStringOffset members are 0.
• The dwStringOffset member is nonzero but dwStringSize is 0.
• The dwStringOffset member is nonzero, dwStringSize is 1, and the byte at the given offset is 0.

See Also

STRINGFORMAT_ Constants