Interrupt 21h Function 71A8h 

Generates an alias (a filename in the 8.3 format) for the specified long filename.

mov ax, 71a8h               ; generate short name

mov si, seg LongFilename    ; see below

mov ds, si

mov si, offset LongFilename

mov di, seg ShortFilename   ; see below

mov es, di

mov di, offset ShortFilename

mov dh, ShortNameFormat     ; see below

mov dl, CharSet             ; see below

int 21h
 

Parameters

LongFilename

Address of null-terminated string that names the long filename to generate an alias for. This string must contain only a filename, not a path.

ShortFilename

Address of null-terminated string that receives the generated alias.

ShortNameFormat

Format for the returned alias (0 is specified for an 11 character directory entry format or 1 for an 8.3 format).

CharSet

Character set of both the long filename and alias. This parameter is a packed 8-bit value with the following form:

One of the following values is specified to indicate the character set for the long filename and alias:

Return Value

Returns the generated alias in the specified buffer if successful.

Remarks

This function generates the alias using the same algorithm that the system uses with the exception that the returned alias will never have a numeric tail. A numeric tail is appended to the end of an alias and consists of the tilde character (~) followed a number. When the system generates an alias, it may attach a numeric tail if the default alias already exists in the current directory. Because this function does not check the current directory to see if the alias already exists, the returned alias will never have a numeric tail. This service is useful for disk utilities that are trying to establish whether the alias, which seems to be associated with a long filename, is correctly associated.