Source Code 1992 March

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Assembly Source File | 1989-03-16 | 24.9 KB | 1,047 lines

page 74,132 title ZIPV - Display directory of ZIP files ; name: ZIPV, version 1, 7 March 1989 ; copyright: 1989, for personal use only; may not be sold. ; author: Vernon D. Buerg ; ; syntax: ; ZIPV [filespec[.ZIP] [/p] [/b] [/c] ; where: ; /p pauses the display after a screen full ; /b suppresses display of d:\path information for bbs use ; /c displays ZIPfile and file comments and extra fields ; ; output: ; - errorlevel returned: ; 0 - normal completion ; 1 - wrong DOS version ; 2 - no files found ; 3 - some invalid ZIP file(s) encountered ; ; notes: ; - supports DOS 3 file sharing ; - requires about 56k of memory, figure 64k for a .COM program ; - assembled using SLR Systems OPTASM; you figure the JMPs for MASM ; - handles self-extracting ZIP files (.EXE type) .xlist print macro name ; display a field mov dx,offset name call prints endm printl macro text ; display a literal local txt,nxt mov dx,offset txt call prints jmp nxt txt db cr,lf,text db stopper nxt equ $ endm save macro reglist ; save registers irp reg, <reglist> push reg endm endm restore macro reglist ; restore registers irp reg, <reglist> pop reg endm endm .list central_dir struc ; from APPNOTES.TXT cd_sig db 02h,01h,4bh,50h ; signature cdver_made db 0,0 ; version made by cdver_ext db 0,0 ; version to extract cd_flag db 0,0 ; general purpose bit flag cd_method dw 0 ; compression method cd_mod_time dw 0 ; last mod time cd_mod_date dw 0 ; last mod date cd_crc dw 0,0 ; crc-32 cd_comp_size dw 0,0 ; compressed size cd_true_size dw 0,0 ; uncompressed size cd_flnm_len dw 0 ; filename length cd_extra_len dw 0 ; extra field length cd_comment_len dw 0 ; file comment length cd_disk_start dw 0 ; disk number start cd_intfile_attr dw 0 ; internal file attributes cd_extfile_attr dw 0,0 ; external file attributes cd_local_offset dw 0,0 ; file offset of local header ; variable length fields follow (boo-hiss) central_dir ends cd_filename equ size central_dir; filename (variable size) cd_extra equ size central_dir; extra field (variable size) cd_comment equ size central_dir; file comment (variable size) central_end struc ; length 22+n ce_sig db 06h,05h,4bh,50h ; signature ce_disk_number dw 0 ; number of this disk ce_disk_start dw 0 ; disk number with central dir start ce_disk_entries dw 0 ; entries in central dir on this disk ce_entries dw 0 ; total entries in central dir ce_size dw 0,0 ; size of central dir ce_offset dw 0,0 ; offset to central dir on this disk ce_comment_len dw 0 ; length of zipfile comment ; variable length fields follow (nerts) central_end ends ce_comment equ size central_end; zipfile comment (variable size) dtantry struc ; DOS Data Transfer Area dtarsvd db 21 dup (0) ; reserved dtaattr db 0 ; attribute dtatime dw 0 ; update time dtadate dw 0 ; update date dtasize dw 0,0 ; size bytes (lo,hi) dtaname db 12 dup (' ') ; name and ext db 0,13,10,255 ; stopper and print dtantry ends subttl ZIPV - Mainline routines page cseg segment public para 'CODE' assume cs:cseg, ds:cseg, ss:cseg, es:cseg org 100h zipv proc far jmp start ; skip around data subttl --- constants, equates and data areas page bel equ 7 ; honker bs equ 8 ; backspace tab equ 9 ; tabski lf equ 10 ; Line Feed cr equ 13 ; la Carriage Return eof equ 26 ; end of file character stopper equ 255 ; ends print strings db bs,bs,bs,' ' ; overlay entry jmp for type usage db cr,lf, 'ZIPV Version 1.07 Copyright (c) 1989 Vernon D. Buerg' db cr,lf, 'For personal use only. May not be sold.' db cr,lf,lf,' Usage: zipv [d:][\path\]filespec[.ZIP] [/p] [/b] [/c]' db cr,lf db cr,lf, ' Where: /P pauses after each screenful' db cr,lf, ' /B suppresses display of d:\path' db cr,lf, ' /C displays comments' db cr,lf,stopper,eof errlvl db 0 ; dos error level returned opencod db 0 ; open code for share flags db 255 ; find-first return code options db 0 ; command options b_parm equ 1 ; /b -bbs display option p_parm equ 2 ; /p -pause at screen full c_parm equ 4 ; /c - display comments stkptr dw 0 ; stack pointer upon entry ce_ptr dw 0 ; offset to central_end dir record ce_count dw 0 ; count of entries in central dir fileptr dw filenm ; spot after d:\path filehdl dw 0 ; file handle ziptitl db cr,lf,'Archive: ',stopper zipname db 13 dup (0),0,stopper ; ZIP file name for heading ; display lines for verbose vhdr db cr,lf db cr,lf,'Name Length Method SF Size now Mod Date Time CRC-32 ' dashes db cr,lf,'============ ======== ======== ==== ======== ========= ====== ========' db stopper vline db cr,lf vname db 14 dup (' ') vsize db ' 0 ' ; acutal file size vstyle db ' ' ; compression method vfactor db ' xx% ' ; compression factor vlength db 10 dup (' ') ; compressed length vdate db 'dd ' ; creation date vmonth db 'mmm ' vyear db 'yy ' vtime db 'hh:mm ' ; creation time vcrc db 'xxxxxxxx' ; crc in hex db stopper len_vline equ $-vline ; length of print line totsf dw 0,0 ; average stowage factor totlen dw 0,0 ; total of file lengths totsize dw 0,0 ; total of file sizes totmbrs dw 0 ; total number of files ; final totals line vthdr db cr,lf,'*total' vtmbrs db ' ' vtsize db 8 dup (' '),' ' db 10 dup (' ') vtsf db ' % ' vtlen db 8 dup (' ') db cr,lf db stopper sign db ' ' vtotal db '*total' ctitle db cr,lf,'Comment: ',stopper cextra db cr,lf,'Extra: ',stopper styles db 'Stored ' ; compression method names db 'Shrunk ' db 'Reduced1' db 'Reduced2' db 'Reduced3' db 'Reduced4' hundred dw 100 ; for computing percentages months db 'Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ' subttl --- Mainline page start: mov sp,offset cs:stk_end ; local stack mov stkptr,sp ; save for dos return mov ah,30h ; get dos version int 21h ; cmp al,2 ; version 2 or later? jb badver ; no, gotta quit cmp al,3 ; enough for share? jb dos_okay ; no, open as-is mov opencod,40h ; yes, add read-only dos_okay: mov bx,paras ; size of program mov ah,4ah ; shrink allocated memory int 21h ; setblock function mov di,offset filenm ; clear operands mov cx,offset stk-filenm ; and work areas mov al,0 ; rep stosb ; subttl --- gather command line parameters page getparm: mov si,82h ; Command tail sub cx,cx ; or cl,byte ptr -2[si] ; test parm length jz getparms ; none, return as-is sw1: lodsb ; scan for switch cmp al,'/' ; loopne sw1 ; or cx,cx ; found one? jz getparms ; no, done mov byte ptr -1[si],cr ; yes, stop command line there jmp sw2a ; and check next character sw2: lodsb ; Next character cmp al,'/' ; Another switch? loopne sw2 ; jcxz getparms ; sw2a: lodsb ; yes, get letter following and al,0dfh ; make upper case dec cx ; jle sw3 ; missing switch sw3: cmp al,'P' ; Pause? jne sw4 ; or options,p_parm ; sw4: cmp al,'B' ; BBS use jne sw5 ; or options,b_parm ; sw5: cmp al,'C' ; display Comments? jne sw2 ; or options,c_parm ; jmp sw2 ; Try for another option subttl --- Gather command operands page ; copy first command line operand as ZIP selection filespec getparms: mov si,80h ; offset to command line sub cx,cx ; its length or cl,byte ptr [si] ; any operand? jnz parm0 ; no, print usage ; display usage jmp zipv_exit ; and quit parm0: inc si ; point to operands parm2: lodsb ; strip leading blanks cmp al,' ' ; loope parm2 ; mov di,offset filenm ; first operand target stosb ; parm3: lodsb ; copy filename cmp al,cr ; end of name? je parm4 ; cmp al,' ' ; don't know why this is here je parm4 ; stosb ; loop parm3 ; parm4: mov si,offset filenm +75 ; end of filename stuff mov cx,76 ; std ; parm5: lodsb ; cmp al,'/' ; funny path delimiter? je parm6 ; cmp al,'\' ; normal path delimiter? je parm6 ; cmp al,':' ; bumped into drive? je parm6 ; loop parm5 ; dec si ; parm6: cld ; add si,2 ; point to where filename goes mov fileptr,si ; and save for later ; add default ZIP extension if necessary mov si,fileptr ; start of filespec mov cx,13 ; parm10: lodsb ; cmp al,0 ; end of name? je parm11 ; cmp al,'.' ; got extension? je parm12 ; loop parm10 ; parm11: mov di,si ; ptr to end of name dec di ; mov ax,'Z.' ; default extension stosw ; mov ax,'PI' ; stosw ; parm12: subttl --- Find matching files page ; ; set up next matching file name process: mov dx,offset dta ; set local dta for murkers mov ah,1ah ; int 21h ; mov dx,offset filenm ; find first matching file sub cx,cx ; normal attribute mov ah,4eh ; int 21h ; mov flags,al ; indicate find-first status or ax,ax ; any return code? jz gotfirst ; nope, continue jmp nofiles ; yup, abort ; set up next matching file name gotfirst: mov si,offset dta+30 ; point to filename found mov di,fileptr ; and overlay old name mov cx,13 ; gotfirst1: lodsb ; next char stosb ; cmp al,0 ; end of name? loopne gotfirst1 ; mov al,0FFh ; append stoppers stosb ; mov si,offset dta+30 ; copy filename for heading mov di,offset zipname ; mov cx,13 ; asciiz filename gotfirst2: lodsb ; next char stosb ; cmp al,0 ; end of name? loopne gotfirst2 ; mov al,0FFh ; append stoppers stosb ; process_loop: ; open the file mov dx,offset filenm ; point to d:\path\filename mov ah,3dh ; open function mov al,opencod ; share parameters int 21h ; issue open jc open_err1 ; oops mov filehdl,ax ; save file handle call posfile ; position and read central directory call close ; release the ZIP file call dispdir ; display directory contents getnext: mov ah,4fh ; get next file name int 21h ; jc alldone ; or ax,ax ; jz gotfirst ; alldone: jmp zipv_exit ; all done subttl --- Display directory entries page ecount dw 0 ; entries on current disk dispdir proc near sub ax,ax ; reset totals counters mov totmbrs,ax ; mov totsize,ax ; mov totsize+2,ax ; mov totlen,ax ; mov totlen+2,ax ; mov totsf,ax ; ; display titles mov ax,ce_count ; number of entries mov ecount,ax ; save as line counter print ziptitl ; test options,b_parm ; want short filename? jz dispdir1 ; no print zipname ; show short name jmp dispdir2 ; dispdir1: print filenm ; show full name ; display comments dispdir2: test options,c_parm ; want them? jz disp3 ; no mov si,ce_ptr ; offset to ce dir mov cx,ce_comment_len[si] ; jcxz disp3 ; if none print ctitle ; yes, add heading item lea dx,ce_comment[si] ; point to comment mov ah,40h ; write to file mov bx,1 ; using std out int 21h ; disp3: print vhdr ; show headings mov bx,offset cdir ; first header in central directory dispdir_loop: mov di,offset vname ; clear print line mov cx,14 ; mov al, ' ' ; rep stosb ; call stowage ; compute stowage factor disp_style: mov si,cd_method[bx] ; compression method code mov cl,3 ; shl si,cl ; time style length add si,offset styles ; list of method names mov di,offset vstyle ; mov cx,8 ; rep movsb ; disp_crc: mov di,offset vcrc ; format crc-32 value mov ax,cd_crc+2[bx] ; first word call cvh ; mov ax,cd_crc[bx] ; second word call cvh ; mov ax,cd_mod_time[bx] ; last modified time call gettime ; format it mov ax,cd_mod_date[bx] ; last modified date call getdate ; format it mov ax,word ptr cd_true_size[bx] ; actual file size mov dx,word ptr cd_true_size+2[bx] ; high word add totsize,ax ; accumulate total size adc totsize[2],dx ; mov si,offset vsize ; call format ; mov ax,word ptr cd_comp_size[bx] ; compressed file size mov dx,word ptr cd_comp_size+2[bx] ; high word add totlen,ax ; accumulate total length adc totlen[2],dx ; mov si,offset vlength ; call format ; mov cx,cd_flnm_len[bx] ; file name length lea si,cd_filename[bx] ; and offset mov di,offset vname ; to print line rep movsb ; inc totmbrs ; total files count print vline ; display an entry ; process extra field dispdir_extra: test options,c_parm ; want comments? jz dispdir_next ; no mov cx,cd_extra_len[bx] ; extra field jcxz dispdir_comment ; if none mov si,cx ; compute offset add si,bx ; to extra field add si,cd_flnm_len[bx] ; print cextra ; lea dx,cd_comment[si] ; point to comment mov ah,40h ; write to file mov bx,1 ; using std out int 21h ; ; display copmment field dispdir_comment: mov cx,cd_comment_len[bx] ; comment field jcxz dispdir_next ; if none mov si,cx ; compute offset add si,bx ; to comments add si,cd_flnm_len[bx] ; add si,cd_extra_len[bx] ; print ctitle ; lea dx,cd_comment[si] ; point to comment mov ah,40h ; write to file mov bx,1 ; using std out int 21h ; ; set-up for next entry dispdir_next: mov cx,size central_dir ; minimum cd entry size add cx,cd_flnm_len[bx] ; plus file name length add cx,cd_extra_len[bx] ; plus extra field length add cx,cd_comment_len[bx] ; plus comment field length add bx,cx ; to point to next entry dec ecount ; jnz dispdir_loop ; continue page ; ; display totals for current file dir_totals: print dashes ; separate totals line mov ax,totsize ; total file sizes mov dx,totsize[2] ; high word mov si,offset vtsize ; call format ; mov ax,totlen ; compressed file size mov dx,totlen[2] ; high word mov si,offset vtlen ; call format ; mov ax,totmbrs ; count of members sub dx,dx ; mov si,offset vtmbrs-2 ; call format ; mov cx,totlen ; compressed file size mov dx,totlen[2] ; high word mov bx,totsize ; actual file size mov ax,totsize[2] ; high word call stow_total ; mov si,offset vtotal ; say *total mov di,offset vthdr+2 ; mov cx,6 ; rep movsb ; print vthdr ; display totals ret ; dispdir endp subttl --- Position file page ; ; Position to end of ZIP file less central directory size margin dw size central_end ; how far before ce to read posfile proc near ; mov margin,size central_end ; how far before ce dir to point posfile_point: mov bx,filehdl ; get file handle mov cx,dta.dtasize[2] ; high word of size mov dx,dta.dtasize ; low word of size sub dx,margin ; less size of central sbb cx,0 ; directory end record jl posfile_start ; if small file mov ax,4200h ; move to central end directory int 21h ; lseek function jmp read_ce ; posfile_start: mov ax,dta.dtasize ; use file size mov margin,ax ; as amount to position jmp posfile_point ; ; read central-directory-end record read_ce: mov cx,margin ; how much to read (pos before eof) mov dx,offset cde ; central end dir area mov ah,3fh ; int 21h ; jc open_err2 ; failed cmp ax,cx ; read it all? jne open_err3 ; nope ; search end of file for cde signature mov bx,offset cde+1 ; point to centerl end dir record mov cx,margin ; look back this far sub cx,size central_end-1 ; add bx,cx ; search_loop: mov si,bx ; next cde byte dec bx ; cmp word ptr [si],4b50h ; check signature jne search_loop1 ; cmp word ptr 2[si],0605h ; je read_cd ; found it search_loop1: loop search_loop ; continue search add margin,256 ; not yet, jmp posfile_point ; back up some more ; re-position to central-directory read_cd: mov ce_ptr,si ; save pointer to c_e dir start mov ax,ce_disk_entries[si] ; number of entries mov ce_count,ax ; and save for later mov dx,ce_offset[si] ; offset to central directory mov cx,ce_offset+2[si] ; mov bx,filehdl ; get file handle mov ax,4200h ; move file pointer int 21h ; returns dx:ax position ; read the central directory until end-of-file mov bx,dta.dtasize[2] ; get file size in bx:cx mov cx,dta.dtasize ; to compute sub cx,ax ; size of sbb bx,dx ; central dir to eof mov bx,filehdl ; get file handle mov ah,3fh ; for reading mov dx,offset cdir ; central dir end area int 21h ; jc open_err4 ; failed cmp ax,cx ; read it all? jne open_err5 ; nope ret ; posfile endp page ; ; compute stowage; reduce the size/length to word values stowage proc near ; compute stowage factor push bx ; save dir pointer mov cx,word ptr cd_comp_size[bx] ; compressed file size mov dx,word ptr cd_comp_size+2[bx] ; high word mov ax,word ptr cd_true_size+2[bx] ; high word mov bx,word ptr cd_true_size[bx] ; actual file size mov si,offset vfactor-5 ; target area jmp stow51 ; stow_total: push bx ; entry for totals calculation mov si,offset vtsf-5 ; target area stow51: or ax,ax ; big number? jz stow52 ; nope, can use it shr ax,1 ; yup, divide by two rcr bx,1 ; shr dx,1 ; rcr cx,1 ; jmp stow51 ; stow52: mov ax,bx ; low word of actual size mov sign,' ' ; cmp ax,cx ; zip member is larger? jb stow520 ; sub ax,cx ; amount saved jmp stow56 ; stow520: sub ax,cx ; neg ax ; mov sign,'-' ; stow56: mul hundred ; to percentage add ax,50 ; adc dx,0 ; round up percent or bx,bx ; empty file? jnz stow53 ; mov ax,100 ; jmp stow54 ; stow53: div bx ; stow54: sub dx,dx ; cmp ax,100 ; archive fouled? jbe stow55 ; sub ax,ax ; stow55: call format ; mov al,sign ; get + or - mov byte ptr [si],al ; pop bx ; restore dir pointer ret ; return to caller stowage endp ; subttl --- subroutines page ; ; close the file close proc near ; mov bx,filehdl ; file handle or bx,bx ; is it open jz close_done ; mov ah,3eh ; close function int 21h ; sub bx,bx ; close_done: mov filehdl,bx ; indicate closed ret ; close endp ; page ; ; print string like int 21h function 9 pause db cr,lf,'... more?$' backup db cr,9 dup (8),'$' linecnt db 0 ; line counter for pause pagecnt db 23 ; lines per screen prints proc near ; dx has offset to string test options,p_parm ; want pausing? jz ps1 ; no, skip next save <bx,cx,dx,si> ; save work regs mov al,linecnt ; cmp al,pagecnt ; end of screen? jbe ps0 ; not yet mov dx,offset pause ; yup, say so mov ah,9 ; int 21h ; mov ah,0 ; get a key int 16h ; mov dx,offset backup ; over write pause prompt mov ah,9 ; int 21h ; mov linecnt,0 ; reset line counter ps0: restore <si,dx,cx,bx> ; restore work regs ps1: save <si,bx,cx> ; save work regs mov si,dx ; sub cx,cx ; ps2: lodsb ; cmp al,stopper ; ending hex ff? je ps8 ; inc cx ; incr text length cmp al,lf ; another line? jne ps2 ; inc linecnt ; jmp ps2 ; ps8: mov ah,40h ; write to file mov bx,1 ; using std out int 21h ; ps9: restore <cx,bx,si> ; recover registers ret ; prints endp page ; ; format the time time record hour:5,min:6,sec:5 ; packed time gettime proc near ; format the date mov di,offset vtime ; push ax ; save date and ax,mask hour ; get hour part mov cl,hour ; bits to shift shr ax,cl ; call cnvrt1 ; stosw ; mov al,':' ; stosb ; gt3: pop ax ; get the time back and ax,mask min ; get min part mov cl,min ; bits to shift call cnvrt ; stosw ; gottime:ret ; gettime endp cnvrt proc near ; convert to ascii shr ax,cl ; cnvrt1: aam ; make al into bcd or ax,'00' ; and to ascii xchg al,ah ; cnvrtd: ret ; cnvrt endp page ; ; format the date date record yr:7,mo:4,dy:5 ; packed date getdate proc near ; format the date push bx ; save cd pointer or ax,ax ; is it zero? jz gotdate ; push ax ; save date and ax,mask yr ; get year part mov cl,yr ; bits to shift call cnvrt ; mov di,offset vyear ; or al,'8' ; adjust for base year stosw ; pop bx ; get the date back push bx ; save it and bx,mask mo ; get month part mov cl,mo ; bits to shift shr bx,cl ; add bx,bx ; form month table index add bx,bx ; lea si,word ptr months-4[bx]; mov cx,3 ; mov di,offset vmonth ; rep movsb ; pop ax ; get the date back and ax,mask dy ; get day part mov cl,dy ; bits to shift call cnvrt ; mov di,offset vdate ; stosw ; gotdate: ; pop bx ; restore cd pointer ret ; back to caller getdate endp page ; ; format 4-byte binary into ASCII for display ddptr dw 0 ; format proc near ; formats a 32 bit integer in dx:ax save <bp,bx,di,si> ; to ds:si mov ddptr,si ; addr of target field mov di,dx ; routine uses di:si mov si,ax ; call printdd ; restore <si,di,bx,bp> ; ret ; printdd: xor ax,ax ; zero out the mov bx,ax ; working mov bp,ax ; registers. mov cx,32 ; # bits of precision j1: shl si,1 ; rcl di,1 ; xchg bp,ax ; call j6 ; xchg bp,ax ; xchg bx,ax ; call j6 ; xchg bx,ax ; adc al,0 ; loop j1 ; mov cx,1710h ; mov ax,bx ; call j2 ; mov ax,bp ; j2: push ax ; mov dl,ah ; call j3 ; pop dx ; j3: mov dh,dl ; shr dl,1 ; move high shr dl,1 ; nibble to shr dl,1 ; the low shr dl,1 ; position call j4 ; mov dl,dh ; j4: and dl,0fh ; mask low nibble jz j5 ; if not zero mov cl,0 ; j5: dec ch ; and cl,ch ; or dl,'0' ; fold in ascii zero sub dl,cl ; mov bx,ddptr ; mov [bx],dl ; ptr to next target field inc ddptr ; ret ; j6: adc al,al ; daa ; xchg al,ah ; adc al,al ; daa ; xchg al,ah ; ret ; format endp page ; ; convert binary word to two hex characters hexchar db '0123456789ABCDEF' ; for conversion cvh proc near ; convert 16-bit binary word in ax save <bx,cx,dx> ; to hex ASCII string at ds:di sub bx,bx ; mov dx,ax ; save 16-bits mov bl,dh ; third nibble mov cl,4 ; shr bl,cl ; mov al,hexchar[bx] ; stosb ; mov bl,dh ; last nibble and bl,0fh ; mov al,hexchar[bx] ; stosb ; mov bl,dl ; first nibble mov cl,4 ; sub bh,bh ; shr bl,cl ; isolate mov al,hexchar[bx] ; stosb ; mov bl,dl ; second nibble and bl,0fh ; isolate mov al,hexchar[bx] ; stosb ; restore <dx,cx,bx> ; restore registers ret ; return cvh endp subttl --- Errors and exits page ; ; error messages and exits errmsg db cr,lf,"ERROR! ",bel,stopper errmsg1 db "Unable to open ",stopper errmsg2 db "Reading central end directory: ",stopper errmsg3 db "Central end directory incomplete: ",stopper errmsg4 db "Reading central directory: ",stopper errmsg5 db "Central directory incomplete: ",stopper open_err1: mov dx,offset errmsg1 ; display message jmp zipv_error ; and quit open_err2: mov dx,offset errmsg2 ; display message jmp zipv_error ; and quit open_err3: mov dx,offset errmsg3 ; display message jmp zipv_error ; and quit open_err4: mov dx,offset errmsg4 ; display message jmp zipv_error ; and quit open_err5: mov dx,offset errmsg5 ; display message jmp zipv_error ; and quit nofiles: printl 'No file(s) found ' ; display message mov errlvl,2 ; set return code jmp zipv_exit ; and quit badver: printl "DOS 2.0 or later is required." mov errlvl,1 ; set return code jmp zipv_exit ; and quit zipv_error: mov sp,cs:stkptr ; insure stack pointer mov errlvl,3 ; return error code push dx ; print errmsg ; make some noise pop dx ; call prints ; display error message print filenm ; with file name cmp flags,255 ; processed any files? jne getnext ; yes, try some more zipv_exit: mov sp,cs:stkptr ; insure stack pointer mov al,errlvl ; get error level mov ah,4ch ; exit int 21h ; subttl --- data areas page filenm equ $ ; command line filespec supplied dta equ filenm+80 ; dos data transfer area cde equ dta+48 ; central directory end record ; with room for 8k of comments cdir equ cde+(size central_end)+(8*1024) ; central directory stk equ cdir+ (52*1024) ; and what's left as room for comments stk_end equ stk+256 ; local stack paras equ (stk_end+256-cseg)/16 ; paragraphs in module zipv endp end zipv