charset.txt

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Routine:  AddChar
-----------------

Category:             Character Set Routine

Registers on Entry:   ES:DI- pointer to first byte of desired set
		      AL- character to add to the set

Registers on Return:  None

Flags affected:       None

Example of Usage:
		      les     di, SetPtr
		      add     di, 1           ;Point at 2nd set in group.
		      mov     al, Ch2Add      ;Character to add to set.
		      addchar


Description:  AddChar lets you add a single character (passed in AL)
	      to a set.

Include:              stdlib.a or charsets.a


Routine:  Rmvchar
-----------------

Category:             Character Set Routine

Registers on entry:   ES:DI (contains the address of first byte of a set)
		      AL    (contains the character to be removed)

Registers on return:  None

Flags affected:	      None

Example of Usage:
		      lea di, SetPtr
		      add di, 7		;Point at eighth set in group.
		      mov al, Ch2Rmv
		      Rmvchar

Description:  This routine removes the character in AL from a set.
	      ES:SI points to the set's mask byte. The corresponding
	      bit in the set is cleared to zero.

Include:              stdlib.a or charsets.a


Routine:  Member
----------------

Category:             Character Set Routine

Registers on entry:   ES:DI (contains the address of first byte of a set)
		      AL    (contains the character to be compared)

Registers on return:  None

Flags affected:       Zero flag (Zero = 0 if the character is in the set
				 Zero = 1 if the character is not in the set)

Example of Usage:
		      les di, SetPtr
		      add di, 1
		      mov al, 'H'
		      member
		      jne IsInSet


Description:  Member is used to find out if the character in AL is in a set
	      with ES:DI pointing to its mask byte. If the character is in
	      the set, the zero flag is set to 0. If not, the zero flag is
	      set to one.

Include:              stdlib.a or charsets.a


Routine:  CopySet
-----------------

Category:            Character Set Routine

Register on entry:   ES:DI- pointer to first byte of destination set.
		     DX:SI- pointer to first byte of source set.

Register on Return:  None

Flags affected:      None

Example of Usage:
		     les     di, SetPtr
		     add     di, 7           ;Point at 8th set in group.
		     mov     dx, seg SetPtr2 ;Point at first set in group.
		     lea     si, SetPtr2
		     copyset


Description:  CopySet copies the items from one set to another.  This is a
	      straight assignment, not a union operation.  After the
	      operation, the destination set is identical to the source set,
	      both in terms of the element present in the set and absent
	      from the set.


Include:             stdlib.a or charsets.a


Routine:  SetUnion
------------------

Category:            Character Set Routine

Register on entry:   ES:DI - pointer to first byte of destination set.
		     DX:SI - pointer to first byte of source set.

Register on return:  None

Flags affected:      None

Example of Usage:    les   di, SetPtr
		     add   di, 7              ;point at 8th set in group.
		     mov   dx, seg SetPtr2    ;point at 1st set in group.
		     lea   si, sSetPtr2
		     unionset


Description:  The SetUnion routine computes the union of two sets.
	      That is, it adds all of the items present in a source set
	      to a destination set.  This operation preserves items
	      present in the destination set before the SetUnion
	      operation.

Include:             stdlib.a or charsets.a


Routine:  SetIntersect
----------------------

Category:            Character Set Routine

Register on entry:   ES:DI - pointer to first byte of destination set.
		     DX:SI - pointer to first byte of source set.

Register on return:  None

Flags affected:      None

Example of Usage:
		     les   di, SetPtr
		     add   di, 7              ;point at 8th set in group.
		     mov   dx, seg SetPtr2    ;point at 1st set in group.
		     lea   si, SetPtr2
		     setintersect

Description:  SetIntersect computes the intersection of two sets, leaving
	      the result in the destination set.  The new set consists
	      only of those items which previously appeared in
	      both the source and destination sets.

Include:             stdlib.a or charsets.a


Routine:  SetDifference
-----------------------

Category:            Character Set Routine

Register on entry:   ES:DI - pointer to the first byte of destination set.
		     DX:SI - pointer to the first byte of the source set.

Register on return:  None

Flags affected:      None

Example of Usage:
		     les   di, SetPtr
		     add   di, 7               ;point at 8th set in group.
		     mov   dx, seg SetPtr2     ;point at 1st set in group.
		     lea   si, SetPtr2
		     setdifference


Description:  SetDifference computes the result of (ES:DI) := (ES:DI) -
	      (DX:SI).  The destination set is left with its original
	      items minus those items which are also in the source set.

Include:             stdlib.a or charsets.a


Routine:  Nextitem
------------------

Category:             Character Set Routine

Registers on entry:   ES:DI (contains the address of first byte of the set)

Registers on return:  AL (contains the first item in the set)

Flags affected:       None

Example of Usage:
		      les di, SetPtr
		      add di, 7		;Point at eighth set in group.
		      nextitem


Description:  Nextitem is the routine to search the first character (item)
	      in the set with ES:DI pointing to its mask byte. AL will
	      return the character in the set. If the set is empty, AL
	      will contain zero.

Include:              stdlib.a or charsets.a


Routine:  Rmvitem
-----------------

Category:             Character Set Routine

Registers on entry:   ES:DI (contains the address fo first byte of the set)

Registers on return:  AL (contains the first item in the set)

Flags affected:       None

Example of Usage:
		      les di, SetPtr
		      add di, 7
		      rmvitem

Description:  Rmvitem locates the first available item in the set and
	      removes it with ES:DI pointing to its mask byte. AL will
	      return the item removed. If the set is empty, AL will
	      return zero.

Include:              stdlib.a or charsets.a