Simtel MSDOS - Coast to Coast/simteldosarchivecoasttocoast2.iso/asmutil/usoftpd.zip/WHAT.ASM

Assembly Source File | 1987-07-31 | 23KB | 794 lines

      TITLE      WHAT

; Program WHAT.ASM
; Purpose Batch    file enhancer
; Input      Command line consisting of:
;         Command letter (with optional E for extended)
;         Optional prompt enclosed in double    quotes
;         Optional argument
; Output  Number in DOS    ERRORLEVEL and string in WHAT environment variable

      DOSSEG
      .MODEL  small
      PAGE      60,120
      INCLUDE DOS.INC

      .STACK  100h

      .DATA
help1      LABEL      BYTE
DB 13,10,"            WHAT - Batch file enhancer",13,10,13,10
DB "Command            Purpose        Argument   Environ       Exit           Extended",13,10
DB "---------        -------        --------   -------       ----           ------",13,10
DB "C[E] [""prompt""]    [chars]    Get        Allowable  Character   Character   Echo",13,10
DB "            character   characters",13,10,13,10
DB "S[E] [""prompt""]        Get string  None       String       Length      Echo",13,10,13,10
DB "D[E]            Check DOS   None       Major       (Major*10)  Minor",13,10
DB "                           version       +Minor      version",13,10,13,10
DB "E[E]            Get environ None       Bytes       Bytes/10    10 bytes",13,10
DB "            bytes left               bytes       in exit",13,10,13,10
DB "F[E] filespec        Get file    Filespec   Kilobytes   Ks/10Ks     10Ks in",13,10
DB "            size             (255=directory)       exit",13,10,13,10
DB "K[E] [driveletter]    Get disk    Drive      Kilobytes   Ks/10Ks     10Ks in",13,10
DB "            space                           exit",13,10,13,10
DB "Press a key to continue . . .$"
help2      LABEL      BYTE
DB 13,"M[E]            Check        None       Kilobytes   Ks/10Ks     10Ks in",13,10
DB "            memory                           exit",13,10,13,10
DB "P            Check for   None       1=yes,0=no  1=yes,0=no  None",13,10
DB "            printer",13,10,13,10
DB "V [number]        Get/Set        New mode   Current or  Current or  None",13,10
DB "            video mode           last mode   last mode",13,10,13,10
DB "7            Check for   None       1=yes,0=no  1=yes,0=no  None",13,10
DB "            coprocessor",13,10,13,10
DB "A            Check for   None       1=yes,0=no  1=yes,0=no  None",13,10
DB "            ANSI driver",13,10,13,10
DB "Y[E]            Get current None       Directory   Level/Drive Drive",13,10
DB "            directory",13,10,"$"

guess      DB      80         ; Prompt for string
actual      DB      ?
string      DB      80 DUP (0)

extend      DB      0         ; Flag    for extended command
vid      DB      3         ; Video mode
ans      DB      27,"[6n$"     ; ANSI    string to get current position
overwrt      DB      8,8,8,8,"    $"; Overwrite ANSI characters
delete      DB      8,8,8,"$"     ; Delete ANSI characters

what      DB      "WHAT="     ; Variable name
lwhat      EQU      $-what

prompt      DW      0         ; Pointer to prompt
lprompt      DW      0         ; Length of prompt
arg      DW      0         ; Pointer to argument
larg      DW      0         ; Length of argument

; Command table

cmds      DB      "CSVDMEKFP7AY" ; Command character list
lcmds      EQU      $-cmds     ;   and length    of list
      EVEN
table      DW      GetChar     ; Command procedure table
      DW      GetStr
      DW      DoVid
      DW      GetDOS
      DW      GetMem
      DW      GetEnvSz
      DW      GetDskSz
      DW      GetFilSz
      DW      VeriPrint
      DW      VeriCop
      DW      VerAnsi
      DW      GetDir
      DW      NoCmd

err1      DB      "Invalid command",7,13,10,"$"
err2      DB      "Out of environment space",7,13,10,"$"
err3      DB      "Must have DOS Version 2.0 or higher",7,13,10,"$"

      .CODE
start:      mov      ax,@DATA        ; Starting execution address
      mov      ds,ax            ; Initialize data segment

      @GetVer            ; Get DOS version
      or      al,al            ; Is it    0?
      jne      DOSOK            ; No? Continue
      @DispStr err3            ; Yes? Quit for    1.x
      int      20h

DOSOK:      mov      si,83h        ; Starting point in PSP
      mov      ax,WORD PTR es:[5Dh]    ; Load command characters
      cmp      al,' '        ; Is it    space?
      jne      isarg            ; If no    argument, show help
      call      Help

isarg:      cmp      ah,'E'        ; Extend flag?
      jne      noextend        ; No? Continue
      inc      extend        ; Yes? Turn on flag and    adjust pointer
      inc      si

noextend: call      GetArg        ; Get argument from command line

      push      es            ; Save and load    DS into    ES
      mov      bx,ds
      mov      es,bx
      mov      di,OFFSET cmds    ; Load pointer to command table
      mov      cx,lcmds+1        ; Load length
      repne      scasb            ; Find position    of command character
      pop      es
      sub      di,(OFFSET cmds)+1    ; Point    to procedure
      shl      di,1            ; Adjust for word addresses
      call      table[di]        ; Call the selected procedure

      push      ax            ; Save
      push      es
      call      DoEnviron        ; Put result in    environment string
      or      ax,ax            ; Test for 0 before
      pop      es            ;   restore
      pop      ax
      jz      done

      cmp      BYTE PTR es:[5Dh],'E'    ; Is it    Environment command
      je      done            ; Yes? Skip message

error2:      @DispStr err2            ; Error    message

done:      @Exit                ; Quit with AL as return code

; End of program - Start of procedures

; Procedure GetChar
; Purpose   Get    a character from user
; Input        Allowable characters pointed to by "arg" (optional)
;        Prompt pointed to by "prompt" (optional)
; Output    Character in AX and    in "string"

GetChar      PROC

      call      ShowPrmpt        ; Display prompt if there is one

readkey:  @GetKey 0,1            ; Get a    key
      cmp      al,13            ; Is it    carriage return?
      jne      notcr            ; Yes? Continue
      mov      al,"~"        ; Call it tilde
                    ;   (use tilde in character list
                    ;    if    you want to accept CR)
notcr:      or      al,al            ; Is it    0 for extended key?
      je      exkey            ; Special case

      mov      bl,al            ; Save a copy and swap
      xchg      ah,al

      call      UpCase        ; Uppercase it

      xchg      ah,al            ; Swap back
      mov      si,arg        ; Load pointer and length of argument
      mov      cx,larg
      jcxz      gotchar        ; If no    argument, quit early

; Compare character to argument    to see if it's valid

argcheck: mov      ah,BYTE PTR es:[si]    ; Get character
      inc      si            ; Increment index

      call      UpCase        ; Convert to uppercase

      cmp      ah,al            ; Is it    in argument?
      je      gotchar        ; Yes? We're done
      loop      argcheck        ;   else check another
      @DispCh 7            ; Checked all, so ring bell
      jmp      SHORT    readkey        ;   and    get another character

gotchar:  push      ax
      cmp      extend,0        ; Is extend flag set?
      jne      noecho        ; Yes? Don't echo
      cmp      bl,"~"        ; Don't echo ~ (alias for CR)
      je      noecho
      @DispCh bl            ; Display valid    character
noecho:      pop      ax
      mov      string,al        ; Put the character in string
      inc      actual        ; Length is one
      ret

exkey:      @GetKey 0,1            ; Get second key in AL
      mov      si,arg        ; Load pointer to argument
      cmp      BYTE PTR es:[si],"`"    ; Is argument grave accent?
                    ;   (use grave in character list if
                    ;    you want to accept    extended keys)
      je      gotext        ; Yes? Extended    character
      @DispCh 7            ; No? Illegal, so ring bell
      jmp      SHORT    readkey        ;   and    get another
gotext:      mov      string[0],'0'        ; Extended flag    value is "0<char>"
      mov      string[1],al
      mov      actual,2        ; Length is 2

      ret
GetChar      ENDP

; Procedure GetStr
; Purpose   Get    a string
; Input        Prompt pointed to by prompt    (optional)
; Output    String in "string";    length to AX

GetStr      PROC

      call      ShowPrmpt        ; Display prompt if there is one

      cmp      extend,1        ; Extend flag true?
      je      password        ; Yes? Then don't echo

      @GetStr guess,0        ; Get string (null-terminated)
      jmp      SHORT    gotstr        ; Done

password: mov      bx,OFFSET string    ; Load offset of string    buffer
      mov      cx,80            ; Maximum count
nextkey:  @GetKey 0,1            ; Get key, no echo
      cmp      al,13            ; Is it    carriage return
      je      gotpass        ; Yes? Done
      mov      [bx],al        ; No? Put key in buffer
      inc      bx            ; Point    to next
      loop      nextkey

gotpass:  sub      bx,OFFSET string    ; Adjust pointer to get    count
      mov      actual,bl        ; Save count

gotstr:      @DispCh 13,10
      mov      ax,bx            ; Save string length
      ret
GetStr      ENDP

; Procedure GetDOS
; Purpose   Get    DOS version
; Input        None
; Output    Major or minor version in "string";    (major *10)+minor in AX

GetDOS      PROC
      @GetVer            ; Get DOS version
      mov      string,al        ; Put major in string
      mov      bh,al            ; Save copy
      mov      al,ah            ; Divide minor to get one digit
      sub      ah,ah            ; Clear    top
      mov      cl,10            ; Divide by 10
      div      cl
      xchg      al,bh            ; Exchange major and minor
      mul      cl            ; Multiply major by 10
      add      al,bh            ; (Major*10)+Minor - 3.2 is now    32
      cmp      extend,1        ; Extend?
      jne      gotver        ; No? Already got it
      mov      string,bh        ; Save number
gotver:      mov      actual,1        ; Save length 1
      add      string,30h        ; Convert to ASCII
      ret
GetDOS      ENDP

; Procedure GetEnvSz
; Purpose   Get    environment bytes available
; Input        None
; Output    Environment    bytes available

GetEnvSz  PROC
      push      es            ; Save ES
      call      GetEnv        ; Get the environment size
      pop      es            ; Restore
      sub      ax,cx            ; Subtract length used from total
                    ;   length to get length remaining
      call      BinToDec        ; Convert to string
      call      Byticize        ; Handle values    too large for byte
      ret
GetEnvSz  ENDP

; Procedure GetFilSz
; Purpose   Get    the size of a specified    file
; Input        Filespec pointed to    by "arg"
; Output    File size

GetFilSz  PROC
      cmp      arg,0            ; File name argument?
      jne      isfile
      call      NoCmd
isfile:      mov      di,arg        ; Point    to start and end of arg
      mov      bx,larg
      mov      BYTE PTR es:[bx+di],0    ; Make null-terminated

      push      ds
      @OpenFil arg,0,es        ; Open file for    reading
      pop      ds
      jc      ferror        ; Error    if carry

notdir:      @GetFilSz ax
      jc      ferror        ; Error    if carry
      mov      cx,1000        ; Convert to thousands
      div      cx
      inc      ax            ; Round    up
      jmp      SHORT    gotsize

ferror:      cmp      ax,5            ; Access denied? Probably a directory
      jne      nofile        ; No file or some other    error
      mov      ax,0FFh        ; Call directory size 255
      jmp      SHORT    gotsize
nofile:      sub      ax,ax            ; Size of nothing is 0

gotsize:  call      BinToDec        ; Convert to string
      call      Byticize        ; Handle large values
      ret
GetFilSz  ENDP

; Procedure GetDskSz
; Purpose   Get    K remaining on specified disk
; Input        Drive letter pointed to by "arg"
; Output    Disk space remaining

GetDskSz  PROC
      sub      ax,ax            ; Assume default drive
      cmp      arg,0            ; Was there an argument?
      je      defdrive        ; No? Got drive
      mov      al,BYTE PTR es:6Dh    ; Yes? Get drive letter
      sub      al,'A'-1        ; Convert to binary
defdrive: @ChkDrv al            ; Get disk space
      cmp      ax,0FFFFh        ; Is drive valid?
      jne      valid
      call      NoCmd
valid:      mul      bx            ; Sectors = sectors/cluster * clusters
      mul      cx            ; Bytes    = bytes/sector * sectors
      mov      cx,1000        ; Convert to thousand
      div      cx
      inc      ax            ; Round    up
      call      BinToDec        ; Convert to string
      call      Byticize        ; Handle large values

      ret
GetDskSz  ENDP

; Procedure GetMem
; Purpose   Get    memory available
; Input        None
; Output    Available memory

GetMem      PROC
      int      12h            ; Get memory available in K
      mov      bx,es            ; Get memory used
      mov      cx,6            ; Convert to K
      shr      bx,cl
      sub      ax,bx            ; Calculate how    much is    left
      sub      dx,dx            ; Clear    DX
      mov      cx,1024        ; Multiply to get bytes
      mul      cx
      mov      cx,1000        ; Divide to get    thousands (not K)
      div      cx
      call      BinToDec        ; Convert to string
      call      Byticize        ; Handle large values
      ret
GetMem      ENDP

; Procedure VeriPrint
; Purpose   See    if LPT1    (PRN) is available
; Input        None
; Output    1 for yes or 0 for no

VeriPrint PROC
      mov      ax,200h        ; Check    printer    status
      sub      dx,dx            ;   for    main parallel printer (port 0)
      int      17h
      xchg      dx,ax            ; Put 0    (for error) in AX
      test      dh,00101001b        ; Are any error    bits on?
      jne      printerr        ; Yes? Leave 0
      test      dh,10010000b        ; Are both operation bits on?
      jz      printerr        ; No? Leave 0
      inc      ax            ; Yes? Return 1
printerr: call      BinToDec        ; Convert to string
      ret
VeriPrint ENDP

; Procedure DoVid
; Purpose   Get    current    video mode and optionally set a    new mode
; Input        New    video mode pointed to by "arg" (optional)
; Output    Current video mode (before change)

DoVid      PROC
      mov      ah,0Fh        ; Get video mode
      int      10h

      cmp      larg,1        ; How many digits in mode?
      jl      gotmode        ; None?    Get out
      push      ax            ; Some?    Save mode
      mov      bx,arg        ; Load address of argument string
      mov      ax,es:WORD PTR [bx]    ; Get address of mode string
      je      one            ; One digit - skip the reverse
      xchg      ah,al            ; Reverse for two digits
      sub      ax,'00'        ; Adjust from ASCII to numeric
      aad                ; Convert to binary
      jmp      SHORT    setmode
one:      sub      al,'0'        ; Convert to numeric
setmode:  sub      ah,ah            ; Set mode
      int      10h
      pop      ax            ; Restore
gotmode:  cbw                ; Extend to AX
      call      BinToDec        ; Convert to string
      ret
DoVid      ENDP

; Procedure VeriCop
; Purpose   Check for coprocessor
; Input        None
; Output    1 for yes or 0 for no

VeriCop      PROC
      int      11h            ; Check    peripherals
      test      al,10b        ; Coprocessor
      mov      ax,0            ; Assume no (don't change flags)
      jz      no87            ; No? Done
      inc      ax            ; Yes? Set to 1
no87:      call      BinToDec        ; Convert to string
      ret
VeriCop      ENDP

; Procedure VerAnsi
; Purpose   Check for ANSI driver
; Input        None
; Output    1 for yes or 0 for no

VerAnsi      PROC

      @DispStr ans            ; Print    ANSI string to get
                    ;   cursor position
      mov      ah,6            ; Check    for key
      mov      dl,0FFh        ;   in buffer
      int      21h
      jnz      ansi            ; Done if ANSI
      @DispStr overwrt        ; Overwrite ANSI string
      sub      ax,ax            ; 0 if not ANSI
      jmp      SHORT    gotansi
ansi:      mov      ax,0C06h        ; Clear    returned ANSI keys
      mov      dl,0FFh        ;   out    of buffer
      int      21h
      @DispStr delete        ; Delete ANSI string
      mov      ax,1            ; Set 1    for true
gotansi:  call      BinToDec        ; Convert to string
      ret
VerAnsi      ENDP

; Procedure GetDir
; Purpose   Get    the current directory or drive
; Input        None
; Output    Current directory or drive in "string"; level or drive number in AX

GetDir      PROC      NEAR
      cmp      extend,1        ; Extend flag true?
      jne      directry        ; No? Get directory

      @GetDrv            ; Yes? Get drive
      mov      ah,al            ; Copy
      add      ah,'A'        ; Convert to drive letter
      mov      string,ah        ; Put character    in string
      inc      actual        ; Length 1
      cbw
      ret

directry: mov      si,OFFSET string    ; Load address for string
      mov      BYTE PTR [si],"\"    ; Insert backslash (DOS    doesn't)
      inc      si            ; Point    to next
      @GetDir si
      sub      cx,cx            ; Count    is zero
      dec      si            ; Move pointer back to start
findback: lodsb                ; Load
      cmp      al,"\"        ; Is it    backslash?
      jne      notslash        ; No? Continue
      inc      dx            ; Yes? Increment level counter
notslash: or      al,al            ; Is it    0?
      loopne  findback        ; No? Repeat

      neg      cx            ; Negate to get    positive count
      mov      actual,cl        ; Put level in variable
      xchg      ax,dx
      ret
GetDir      ENDP

; Procedure NoCmd
; Purpose   Return error for invalid command
; Input        None
; Output    None

NoCmd      PROC
      @DispStr err1            ; Display error    and quit
      @Exit      0
NoCmd      ENDP

; Procedure Byticize
; Purpose   Adjust word    values to fit in a byte
; Input        Value in AX
; Output    255    for word values, else value (no    extend)    or value*10 (extend)

Byticize  PROC
      cmp      extend,0        ; Is extend flag set?
      je      sizechk        ; No? Check size
      sub      dx,dx            ; Yes? Clear DX
      mov      bx,10            ; Divide by 10 to get 10-unit chunks
      div      bx

sizechk:  or      ah,ah            ; Is it    255 or less?
      je      byteOK
      mov      al,0FFh        ; No? Call it 255
byteok:      ret
Byticize  ENDP

; Procedure GetArg
; Purpose   Parse command line for argument and    prompt strings
; Input        Command line
; Output    Pointer to argument    in "arg"; length (or 0 if none)    in "larg"
;        Pointer to prompt in "prompt"; length (or 0    if none) in "lprompt"

GetArg      PROC
      push      ax
      push      es            ; Swap ES and DS
      push      ds
      pop      es
      pop      ds

white:      lodsb                ; Load while white space
      cmp      al,' '        ; Is it    space?
      je      white            ; Throw    away
      cmp      al,9            ; Is it    tab?
      je      white            ; Throw    away
      cmp      al,'"'                ; Is it quote?
      je      promptit        ; Process
      cmp      al,13            ; Is it    carriage return?
      je      gotarg        ; Done

      sub      cx,cx
qdone:      dec      si            ; Adjust
      mov      es:arg,si        ; Save pointer to argument start

chars:      lodsb                ; Load while not white
      cmp      al,' '        ; Is it    space?
      je      nomore        ; Done
      cmp      al,9            ; Is it    tab?
      je      nomore        ; Done
      cmp      al,13            ; Is it    carriage return?
      loopne  chars            ; Throw    away
nomore:      not      cx            ; Adjust count
      mov      es:larg,cx        ; Save length
      jmp      SHORT    gotarg

promptit: mov      di,si            ; Save pointer to start
      sub      cx,cx            ; Clear    count
inprompt: lodsb                ; Another
      cmp      al,13            ; Is it    carriage return?
      je      oneq            ; Yes? Treat one quote like character
      cmp      al,'"'                ; Is it quote?
      loopne  inprompt        ; No? Throw away
      mov      es:prompt,di        ; Save prompt pointer
      not      cx
      mov      es:lprompt,cx        ;   and    length
      jmp      SHORT    white        ; Get the argument

oneq:      mov      si,di            ; Restore
      mov      cx,-1            ; Set count to -1
      jmp      SHORT    qdone

gotarg:      push      es            ; Swap ES and DS back
      push      ds
      pop      es
      pop      ds

      pop      ax
      ret
GetArg      ENDP

; Procedure ShowPrmpt
; Purpose   If prompt, display it
; Input        Pointer to prompt
; Output    Prompt to screen

ShowPrmpt PROC
      cmp      prompt,0        ; Is there a prompt?
      je      noshow        ; If not, continue
      push      ds            ; Save and restore DS
      @Write  prompt,lprompt,,es    ; DOS Write function
      pop      ds

noshow:      ret
ShowPrmpt ENDP

; Procedure DoEnviron
; Purpose   Convert a string to    an environment variable
; Input        String in "string"
; Output    String in "WHAT" environment variable;
;          AX has 0 for success, nonzero for    failure

DoEnviron PROC
      call      GetEnv        ; Get environment size,    length,    address
      mov      dx,ax            ; Save size and    length
      mov      bx,cx

; Find "WHAT="

      sub      di,di            ; Point    to start
      sub      al,al            ; Search for zero
      mov      si, OFFSET what    ; Point    source at "WHAT="
findwh:      repne      scasb            ; Search
      cmp      BYTE PTR es:[di],0    ; If double null, end of environment
      je      gotend
      jcxz      noroom        ; Error    if not found
      push      di            ; Save
      push      cx
      mov      si,OFFSET what    ; Load address and length of "what"
      mov      cx,lwhat        ;   for    comparison
      repe      cmpsb            ; Compare
      mov      si,di            ; Make copy
      pop      cx            ; Restore
      pop      di
      jnz      findwh

; Find end of "WHAT" variable

      xchg      di,si
      repne      scasb            ; Find end of environment variable
      xchg      si,di            ; Point    source to next variable

; Calculate characters left to write

      mov      cx,bx            ; Load total characters
      sub      cx,si            ; Subtract finished to get left

; Move everything back to overwrite "WHAT="

movenv:      push      ds            ; Save DS
      mov      ax,es            ; Copy to ES
      mov      ds,ax
      rep      movsb            ; Copy
      mov      BYTE PTR es:[di],0    ; Put null at end in case of error
      pop      ds            ; Restore

; Check    environment space

gotend:      mov      al,actual        ; Load length of string
      sub      ah,ah            ; Clear    top
      add      ax,lwhat        ; Add length of    name
      add      ax,di            ; Add position to get final length
      cmp      ax,dx            ; Is it    longer than environment?
      jge      noroom        ; Yes? Quit

; Put WHAT= at end

      mov      si,OFFSET what    ; Load address and length of what
      mov      cx,lwhat
      rep      movsb

; Put new string at end

      mov      si,OFFSET string    ; Load address and length of string
      mov      cl,actual
      rep      movsb
      mov      WORD PTR es:[di],0    ; Put double null at end
      sub      ax,ax            ; Return 0 for success
      ret

noroom:      inc      ax            ; Return nonzero for fail
      ret
DoEnviron ENDP

; Procedure GetEnv
; Purpose   Find and measure the environment
; Input        None
; Output    Segment of environment in ES, size in AX, length in    CX

GetEnv      PROC
      mov      dx,es:10h        ; Load segment of COMMAND.COM
      mov      es,dx            ;   into ES
      mov      ax,es:2Ch        ; Load COMMAND.COM's environment
      or      ax,ax            ; Is it    0?
      jnz      secondry        ; No? This is a    secondary command
                    ;   and    we have    its environment    in AX
      dec      dx            ; Yes? This is original    COMMAND.COM
      mov      es,dx            ;   so point ES    to paragraph before PSP
      add      dx,es:03        ; Offset of environment    is 3 bytes in
      add      dx,2            ; Adjust it back to PSP
      mov      ax,dx            ; Put it in AX
secondry:

; Note:
; CodeView cannot debug    the previous section of    code, because the PSP
; addresses checked by the code    are those passed from DOS to CodeView,
; not addresses    passed from DOS    to the program.    To debug with CodeView,
; find the actual address of the environment:

;     S    500:0 L    FFFF "COMSPEC="

; When you find    the actual address, hard code it into your program:

;      mov      ax,110Ch        ; Debug    line

; Comment the line out for final assembly after    debugging.

      mov      si,ax            ; Save a copy
      sub      dx,dx            ; Clear    DX for multiply
      dec      ax            ; Get paragaraph before    environment
      mov      es,ax            ; Load into DS
      mov      ax,es:03        ; Size in paragraphs is    at byte    4
      mov      cx,16            ; Multiply by 16
      mul      cx
      mov      es,si            ; Restore environment address
      sub      di,di            ; Point    to start
      mov      cx,ax            ; Load maximum count (size of
      mov      bx,ax            ;   environment) and save a copy
      sub      ax,ax            ; Search for double null
null2:      repne      scasb            ; Look for null
      jz      noerr            ; If not out of    space, continue
      sub      ax,ax            ;   else error (return 0)
      jmp      error2
noerr:      cmp      BYTE PTR es:[di],0    ; Is it    double null?
      jne      null2            ; No? Look again
      mov      cx,di            ; Yes? Save length in CX
      mov      ax,bx            ; Reload size to AX

      ret
GetEnv      ENDP

; Procedure BinToDec
; Purpose   Convert binary number in AX    to string
; Input        Value in AX
; Output    Value string in "string"; length of    string in "actual"

; AL contains number to    be converted

BinToDec  PROC
      push      ax
      push      es
      sub      cx,cx            ; Clear    counter
      mov      bx,10            ; Get ready to divide by 10

getdigit: sub      dx,dx            ; Clear    top
      div      bx            ; Remainder is last digit
      add      dl,'0'        ; Convert to ASCII
      push      dx            ; Put on stack
      inc      cx            ; Count    character
      or      ax,ax            ; Is quotient 0?
      jnz      getdigit        ; No? Get another

      mov      actual,cl        ; Save number of digits
      mov      ax,ds            ; Load DS to ES
      mov      es,ax
      mov      di,OFFSET string    ; Load source

putdigit: pop      ax            ; Get a    digit off stack
      stosb                ; Store    it to string
      loop      putdigit

      pop      es
      pop      ax
      ret
BinToDec  ENDP

; Procedure UpCase
; Purpose   Convert a character    to uppercase
; Input        Character in AH
; Output    Converted character    in AH

UpCase      PROC

      cmp      ah,"a"        ; Is character below lowercase?
      jl      ok            ; If so, continue
                    ;   else
      cmp      ah,"z"        ; Is character above lowercase?
      jg      ok            ; If so, continue
                    ;   else
      sub      ah,20h        ; Make it lowercase
ok:      ret
UpCase      ENDP

; Procedure Help
; Purpose   Display syntax screens
; Input        None
; Output    Help to screen

Help      PROC
      @DispStr help1        ; First    screen
      @GetKey            ; Pause
      @DispStr help2        ; Second screen
      @Exit      0
Help      ENDP

      END     start            ; End assembly