conv.txt

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		      mov     es, di
		      lea     di, buffer
		      mov     ax, -1234
		      ITOA2		      ;Leaves string in BUFFER and
					      ;ES:DI pointing at end of string.


Description:    UTOAx converts a 16-bit unsigned integer value in AX to a
		string of characters which represents that value.  UTOA,
		UTOA2, and UTOAM behave in a manner analogous to ITOAx.  See
		the description of those routines for more details.


Include:       stdlib.a or conv.a



Routine:   HTOA (2,M)
---------------------

Category:            Conversion Routine

Registers on entry:   AL - 8-bit integer to convert to a string
		      ES:DI- Pointer to buffer to hold result (HTOA/HTOA2
			     only).

Registers on Return:  ES:DI- Pointer to string containing converted
		      characters (HTOA/HTOAM only).
		      ES:DI- Pointer to zero-terminating byte of converted
			     string (HTOA2 only).

Flags affected:      Carry set denotes memory allocation error (HTOAM only)


Description:    The HTOAx routines convert an 8-bit value in AL to the two-
		character hexadecimal representation of that byte.  Other
		that that, they behave just like ITOAx/UTOAx.  Note that
		the resulting buffer must have at least three bytes for
		HTOA/HTOA2.


Include:        stdlib.a or conv.a


Routine:  WTOA (2,M)
--------------------

Category:             Conversion Routine

Registers on Entry:   AX- 16-bit value to convert to a string
		      ES:DI- Pointer to buffer to hold result (WTOA/WTOA2
			     only).

Registers on Return:  ES:DI- Pointer to string containing converted
		      characters (WTOA/WTOAM only).
		      ES:DI- Pointer to zero-terminating byte of converted
			     string (WTOA2 only).

Flags Affected:       Carry set denotes memory allocation error (WTOAM only)

Example of Usage:
		      Like WTOA above


Description:  WTOAx converts the 16-bit value in AX to a string of four
	      hexadecimal digits. It behaves exactly like HTOAx except
	      it outputs four characters (and requires a five byte buffer).


Include:        stdlib.a or conv.a



Routine:  LTOA (2,M)
--------------------

Category:             Conversion Routine

Registers on entry:   DX:AX (contains a signed 32 bit integer)
		      ES:DI- Pointer to buffer to hold result (LTOA/LTOA2
			     only).

Registers on Return:  ES:DI- Pointer to string containing converted
		      characters (LTOA/LTOAM only).
		      ES:DI- Pointer to zero-terminating byte of converted
			     string (LTOA2 only).

Flags affected:       Carry set if memory allocation error (LTOAM only)


Example of Usage: 
			mov	di, seg buffer	;Get address of storage
			mov	es, di		; buffer.
			lea	di, buffer
			mov	ax, word ptr value
			mov	dx, word ptr value+2
			ltoa

Description:    LtoA converts the 32-bit signed integer in DX:AX to a string
		of characters.  LTOA stores the string at the address specified
		in ES:DI (there must be at least twelve bytes available at
		this address) and returns with ES:DI pointing at this buffer.
		LTOA2 works the same way, except it returns with ES:DI
		pointing at the zero terminating byte.  LTOAM allocates
		storage for the string on the heap and returns a pointer
		to the string in ES:DI.

Include:        stdlib.a or conv.a



Routine:  ULTOA (2,M)
---------------------

Category:             Conversion Routine

Registers on Entry:   DX:AX- Unsigned 32-bit value to convert to a string
		      ES:DI- Pointer to buffer to hold result (LTOA/LTOA2
			     only).
Registers on Return:  ES:DI- Pointer to string containing converted
		      characters (LTOA/LTOAM only).
		      ES:DI- Pointer to zero-terminating byte of converted
			     string (LTOA2 only).

Flags Affected:       Carry is set if malloc error (ULTOAM only)

Example of Usage:  
                      Like LTOA


Description:  Like LTOA except this routine handles unsigned integer values.

Include:	stdlib.a or conv.a



Routine:  SPrintf (2,M)
-----------------------

Category:            Conversion Routine
		     In-Memory Formatting Routine

Registers on entry:  CS:RET - Pointer to format string and operands of the
			      sprintf routine
		     ES:DI-   Address of buffer to hold output string
			      (sprintf/sprintf2 only)

Register on return:  ES:DI register - pointer to a string containing
				      output data (sprintf/sprintfm only).
				      Pointer to zero-terminating byte at the
				      end of the converted string (sprintf2
				      only).

Flags affected:      Carry is set if memory allocation error (sprintfm only).

Example of Usage:
		     sprintfm
		     db      "I=%i, U=%u, S=%s",13,10,0
		     db      i,u,s
		     puts
		     free


Description:   SPrintf is an in-memory formatting routine. It is similar to
	       C's sprintf routine.

	       The programmer selects the maximum length of the output string.
	       SPrintf works in a manner quite similar to printf, except sprintf
	       writes its output to a string variable rather than to the stdlib
	       standard output.

	       SPrintfm, by default, allocates 2048 characters for the string
	       and then deallocates any unnecessary storage.  An external
	       variable, sp_MaxBuf, holds the number of bytes to allocate upon
	       entry into sprintfm.  If you wish to allocate more or less than
	       2048 bytes when calling sprintf, simply change the value of this
	       public variable (type is word).  Sprintfm calls malloc to
	       allocate the storage dynamically.  You should call free to
	       return this buffer to the heap when you are through with it.

	       Sprintf and Sprintf2 expect you to pass the address of a buffer
	       to them.  You are responsible for supplying a sufficiently
	       sized buffer to hold the result.

Include:             stdlib.a or conv.a



Routine:  SScanf
----------------

Category:              Conversion Routine
		       Formatted In-Memory Conversion Routine

Registers on Entry:    ES:DI - points at string containing values to convert

Registers on return:   None

Flags affected:	       None

Example of Usage:

	      ; this code reads the values for i, j, and s from the characters
	      ; starting at memory location Buffer.

		       les   di, Buffer
		       SScanf
		       db    "%i %i %s",0
		       dd     i, j, s


Description:  SScanf provides formatted input in a fashion analogous to scanf.
              The difference is that scanf reads in a line of text from the
              stdlib standard input whereas you pass the address of a sequence
              of characters to SScanf in es:di.


Include:                stdlib.a or conv.a




Routine:  ToLower
-----------------

Category:            Conversion Routine

Register on entry:   AL- Character to (possibly) convert
				to lower case.

Register on return:  AL- Converted character.

Flags affected:      None

Example of usage:
		     mov     al, char
		     ToLower


Description:  ToLower checks the character in the AL register, if it is upper
	      case it converts it to lower case.  If it is anything else,
	      ToLower leaves the value in AL unchanged.  For high performance
	      this routine is implemented as a macro rather than as a
	      procedure call.  This routine is so short you would spend more
	      time actually calling the routine than executing the code inside.
	      However, the code is definitely longer than a (far) procedure
	      call, so if space is critical and you're invoking this code
	      several times, you may want to convert it to a procedure call to
	      save a little space.


Include:             stdlib.a or conv.a



Routine:   ToUpper
------------------

Category:             Conversion Routine

Registers on Entry:   AL- Character to (possibly) convert to upper case

Registers on Return:  AL- Converted character

Flags Affected:       None

Example of Usage:
		      mov  al, char
		      ToUpper


Description:  ToUpper checks the character in the AL register, if it is lower
	      case it converts it to upper case.  If it is anything else,
	      ToUpper leaves the value in AL unchanged.  For high performance
	      this routine is implemented as a macro rather than as a
	      procedure call (see ToLower, above).


Include:              stdlib.a or conv.a