******************************* DATA ************************************* ASMLIB data manipulation subroutines Copyright (C) 1991 - 1993 Douglas Herr all rights reserved 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� CHRDEL: deletes a character from a string CHRNDEL: deletes a character from a string of known length The resulting space is closed by moving the remaining characters forward Source: chrdel.asm (strlen.asm) Call with: DS:[BX] pointing to an ASCIIZ string (chrndel only) CX = current string length AX = offset from DS:[BX] to character to delete Returns: CX = new string length Uses: CX Example: lea bx,string ; DS:[BX] points to string mov ax,3 ; delete character at DS:[BX+3] call chrdel ; delete the character, shorten string 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� COLORATTR: calculate a color attribute for ASMLIB's text-mode subroutines. Intended for 16-color text modes. Source: coloratt.asm Call with: AL = foreground color (0 - 15) AH = background color (0 - 15) Returns: AH = color attribute Uses: AX Example: include asm.inc mov al,hired ; bright red mov ah,blue ; blue call colorattr ; this should get their attention mov warning,ah ; save the attribute 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� CSET: centers a string in a fixed field Source: cset.asm (strlen.asm) Call with: ES:[DI] = address of field string DS:[SI] = address of string to be centered in the field Both strings must be zero-terminated (ASCIIZ). The field string may not contain any nul characters except for the terminator. Returns: CF = 0 if no error CF = 1 if string was truncated to fit in the field Uses: CF; all other flags and registers are saved Example: mov ax,@data ; in this case, both strings mov ds,ax ; are in DGROUP mov es,ax assume es:@data, ds:@data lea di,field ; field string lea si,source ; string to be centered in field call cset 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� DAYNAME: returns a pointer to an ASCII string for specified day of the week Source: dname.asm (a$mname.asm) Call with: AX = day of week (1 - 7, Sunday = 1) Returns: ES:[BX] = pointer to day name string CX = length of new string Note that the day name string is not zero-terminated strndup may be used to copy the string to the near heap Uses: ES, BX, CX Example: mov ax,day call dayname 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� FILL4, FILL4b: fill a buffer with specified 4-byte data Source: small & medium: fill4.asm huge: fill4.asm (lowES2hi.asm) Call with: DS:[SI] pointing to 4-byte data (integer, float or other) ES:[DI] pointing to buffer CX = number of 4-byte data blocks to fill in buffer Fill4b: BX = byte increment between data blocks Returns: nothing Uses: nothing Example: include asm.inc extrn fill4:proc .data wonowon dd 101. ; float4 value farseg dw ? ; program allocates buffer, stores seg address here .code program fragment assumes DS:@data . . . mov es,farseg xor di,di ; start at beginning of far segment lea si,wonowon ; fill every other 4-byte block in far segment mov bx,8 ; skip 4 bytes between data blocks mov cx,25 ; do it 25 times cal fill4 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� FILL8, FILL8b: fill a buffer with specified 8-byte data Source: small & medium: fill8.asm huge: fill8.asm (lowES2hi.asm) Call with: DS:[SI] pointing to 8-byte data (integer, float or other) ES:[DI] pointing to buffer CX = number of 8-byte data blocks to fill in buffer Fill8b: BX = byte increment between data blocks Returns: nothing Uses: nothing Example: see Fill4 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� FSTRISTR: search for a string in a disk file, case insensetive Source: fstristr.asm (strlen.asm, $strstr.asm, strnupr.asm) FSTRSTR: search for a string in a disk file, case sensetive Source: fstrstr.asm (strlen.asm, $strstr.asm) Call with: BX = file handle, DS:[SI] points to string to find The file must have been opened with read access, and at least 64k DOS memory must be free. See STARTUP.ASM and ENDPROG.ASM. Returns: if CF = 0, DX:AX is the offset of the string in the file if CF = 1: memory not available if AX = DX = 0 string not found if AX = DX = -1 error reading file if AX = DX = -2 Uses: AX, DX, flags Example: extrn fstrstr:proc .data string db 'A String In The File',0 filename db 'anyold.fil',0 .code yoursub proc mov dx,offset filename mov ax,3D00h ; open the file with read access int 21h jc no_good mov bx,ax mov si,offset string ; DS:[SI] points to the string call fstrstr jc no_good ; returns with DX = high word of ; string position, AX = low word 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� GETCMD: isolates command line parameters GetCMD assumes that parameters are separated by one or more spaces Source: getcmd.asm Call with: ES = PSP segment (see STARTUP.ASM; not requried with TINY model) AX = parameter number (first command line parameter = 0) Returns: ES:[BX] pointing to command line parameter CX = length of parameter string CX = 0 if no command parameter(AX) Note: the string at ES:[BX] is not zero-terminated Uses: BX Example: include asm.inc extrn getcmd:proc .data extrn pspseg:word ; PSP segment saved by startup code .code . . . mov es,pspseg mov ax,0 ; get first parameter call getcmd ; returns with ES:[BX] pointing to parameter ; and CX = length of parameter jcxz no_parameters 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� I2TOSTR: convert an integer value to an ASCIIZ string Source: i2tostr.asm I4TOSTR: convert a long integer value to an ASCIIZ string Source: i4tostr.asm ASMLIB's TPrint, GPrint and other 'print' subroutines require a string argument. Numeric data must be converted to a string before printing. Call with: DS:[SI] pointing to a buffer space (i2tostr) AX = integer value (i4tostr) DX:AX = long integer value i2tostr requires a 7-byte (or greater) buffer; i4tostr requires a 12-byte (or greater) buffer Returns: ASCIIZ string at DS:[SI]; numerals are right-justified Uses: nothing; all registers and flags are saved Supports: (i2tostr) signed 2-byte integers (i4tostr) signed 4-byte integers Example: include asm.inc extrn i2tostr:proc .data nbuffer db 7 dup(?) .code . . . mov ax,@data mov ds,ax ; numeric buffer is in DGROUP assume ds:@data lea si,nbuffer mov ax,32750 ; integer value call i2tostr 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� LOWDS2HI: converts low DS:high SI address to high DS:low SI this is handy for data structures over 64k Source: lowds2hi.asm Call with: DS:[SI] = address to convert Returns: DS:[SI] = converted address; SI <= 15 Uses: DS, SI; all other registers and flags are saved Example: extrn lowDS2hi:proc .code . . . mov ds,hugeseg mov si,next_data call lowDS2hi ; ready to address next (65535-15) bytes 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� LOWES2HI: converts low ES:high DI address to high ES:low DI this is handy for data structures over 64k Source: lowes2hi.asm Call with: ES:[DI] = address to convert Returns: ES:[DI] = converted address; DI <= 15 Uses: ES, DI; all other registers and flags are saved Example: extrn lowES2hi:proc .code . . . mov es,hugeseg mov di,next_data call lowES2hi ; ready to address next (65535-15) bytes 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� LSET: left-justifies a string in a fixed field Source: lset.asm (strlen.asm) Call with: ES:[DI] = address of field string DS:[SI] = address of string to be justified in the field Both strings must be zero-terminated (ASCIIZ). The field string may not contain any NUL characters except for the terminator. Returns: CF = 0 if no error CF = 1 if string was truncated to fit in the field Uses: CF all other flags and registers saved Example: mov ax,@data ; in this case, both strings mov ds,ax ; are in DGROUP mov es,ax assume es:@data, ds:@data lea di,field ; field string lea si,source ; string to be justified in field call lset 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� LTRIM: remove leading blanks from an ASCIIZ string Source: ltrim.asm (strlen.asm) Call with: DS:[BX] pointing to string Returns: CX = new string length Uses: CX Example: lea bx,string call ltrim 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� MAXI2, MAXI2b: find maximum value in a signed integer array Source: small & medium models: maxi2.asm huge model: maxi2.asm (lowDS2hi.asm) MINI2, MINI2b: find minimum value in a signed integer array Source: small & medium models: mini2.asm huge model: mini2.asm (lowDS2hi.asm) MAXU2, MINU2b: find maximum value in an unsigned integer array Source: small & medium models: maxu2.asm huge model: maxu2.asm (lowDS2hi.asm) MINU2, MINU2b: find minimum value in an unsigned integer array Source: small & medium models: minu2.asm huge model: minu2.asm (lowDS2hi.asm) Call with: ES:[DI] pointing to the array CX = number of array elements For max/min?2b, call with BX = byte increment between array elements. Max/min?2 assume increment = 2. Returns: AX = array element number with maximum value see example to calculate address of maximum value if subroutine was called with CX = 0, CF = 1 Uses: AX, CF Example: include asm.inc extrn maxi2:proc .data integers dw 140 dup(0) .code . ; program establishes array values . . mov ax,@data mov es,ax assume es:@data lea di,integers mov cx,140 ; search the entire array call maxi2 shl ax,1 ; convert word offset to byte offsest add di,ax ; ES:[DI] points to the maximum value ; With max/min?2b, the offset of the ; value is DI + (AX * BX). 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� MAXI4, MAXI4b: find maximum value in a signed 4-byte integer array Source: small & medium models: maxi4.asm huge model: maxi4.asm (lowDS2hi.asm) MINI4, MINI4b: find minimum value in a signed 4-byte integer array Source: small & medium models: mini4.asm huge model: mini4.asm (lowDS2hi.asm) MAXU4, MAXU4b: find maximum value in an unsigned 4-byte integer array Source: small & medium models: maxu4.asm huge model: maxu4.asm (lowDS2hi.asm) MINU4, MINU4b: find minimum value in an unsigned 4-byte integer array Source: small & medium models: minu4.asm huge model: minu4.asm (lowDS2hi.asm) Call with: ES:[DI] pointing to the array CX = number of array elements For max/min?4b, call with BX = byte increment between array elements. Max/min?4 assume increment = 4. Returns: AX = array element number with maximum value see example to calculate address of maximum value. if subroutine was called with CX = 0, CF = 1 Uses: AX, CF Example: include asm.inc extrn maxi4:proc .data int4 dd 140 dup(0) .code . ; program establishes array values . . mov ax,@data mov es,ax assume es:@data lea di,int4 mov cx,140 ; search the entire array call maxi4 shl ax,1 ; convert dword offset to word offset shl ax,1 ; convert word offset to byte offset add di,ax ; ES:[DI] points to the maximum value ; With max/min?4b, the offset of the ; value is DI + (AX * BX). 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� MONTHNAME: returns a pointer to an ASCII string for specified month Source: mname.asm (a$mname.asm) Call with: AX = month (1 - 12, January = 1) Returns: ES:[BX] = pointer to month name string CX = length of month string Note that the month name string is not zero-terminated strndup may be used to copy the string to the near heap Uses: ES, BX, CX Example: mov ax,month call monthname jc no_memory 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� NFORMAT: formats a numeric string Source: nformat.asm (ltrim.asm, strspace.asm, heap.asm) Call with: DS:[SI] pointing to a numeric string (such as one produced by i4tostr or i2tostr) AL = number of decimal places in output string BL = option code where option 1 = negative numbers enclosed with parentheses option 2 = commas between thousands option 4 = decimals truncated (instead of rounded) assumes DS @data Note: you must initialize the near heap with HINIT before using NFORMAT. See STARTUP.ASM. Returns: DS:[BX] pointing to formatted ASCIIZ string Uses: BX, CF Example: include asm.inc extrn nformat:proc, i2tostr:proc extrn hinit:proc .data ; reserve space for the heap heapsize equ 3000 ; should be plenty hbuffer db heapsize dup (0) ; I'll use this numeric buffer nbuffer db 12 dup(0) .code ; program fragment assumes DS:@data . . . lea bx,hbuffer mov ax,heapsize call hinit mov ax,-12345 lea si,nbuffer call i2tostr mov al,2 ; 2 decimal places mov bl,1 OR 2 ; I want parentheses and commas call nformat ; result returned at DS:[BX] ; remember to release the formatted ; string space with HFREE when you're ; done with the string 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� PATH: finds paths in program enviornment isolates each path in "PATH=" part of enviornment Source: path.asm (strlen.asm) Call with: ES = PSP segment, AX = path number. See STARTUP.ASM. Returns: ES:[BX] -> path(AX) in enviornment block, CX = length of path If CX = 0, path(AX) does not exist. The first path in the enviornment is path(0). Note that the path string at ES:[BX] is NOT zero-terminated. Uses: BX, CX, ES; flags and all other registers are saved Example: ; program startup code saves PSP segment include asm.inc extrn path:proc stacksize equ 1024 .stack stacksize .data public pspseg pspseg dw ? ; storage for PSP segment .code includelib asmlib start: ; start by pointing DS to DGROUP mov ax,@data mov ds,ax assume ds:@data ; save PSP segment mov pspseg,es . . . ; sometime later in the program xor ax,ax ; start with the first path find_path: mov es,pspseg call path jcxz no_path ; exit if no more paths, or else copy CX bytes ; at ES:[BX] to some useful location (try ; strndup). inc ax ; look for next path jmp find_path no_path: 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� QFNAME: qualifies a filename Source: qfname.asm Call with: DS:[BX] pointing to a filename; the filename may contain drive specification and/or complete or partial path name. Drive specification and path name not required. Returns: DS:[SI] pointing to the full DRIVESPEC:\PATH\FILENAME CX = length of full filename Note that DS:[SI] points to QFName's buffer space; the next call to QFName will return a new filename at the same address. Uses: SI, CX, flags Example: include asm.inc .data docs db '*.doc',0 ; search for .DOC files in current directory .code . . . mov ax,@data mov ds,ax lea bx,docs call qfname ; returns 'drive:\path\*.doc' 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� RANDOM: generates a near-random number Source: random.asm Call with: no parameters Returns: AX = near-random number between 0 and 65535 you may notice repeating patterns every few thousand calls to Random. Uses: AX Example: call random 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� RSET: right-justifies a string in a fixed field Source: rset.asm (strlen.asm) Call with: ES:[DI] = address of field string DS:[SI] = address of string to be justified in the field Both strings must be zero-terminated (ASCIIZ). The field string may not contain any nul characters except for the terminator. Returns: CF = 0 if no error CF = 1 if string was truncated to fit in the field Uses: CF; all other flags and registers saved Example: mov ax,@data ; in this case, both strings mov ds,ax ; are in DGROUP mov es,ax assume es:@data, ds:@data lea di,field ; field string lea si,source ; string to be justified in field call rset 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� RTRIM: removes trailing blanks from an ASCIIZ string Source: rtrim.asm (strlen.asm) Call with: DS:[BX] pointing to string Returns: CX = new string length Uses: CX Example: lea bx,string call rtrim 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� SORTI4HI: sort a signed array of 4-byte integers, highest first Source: sorti4hi.asm SORTI4LO: sort a signed array of 4-byte integers, lowest first Source: sorti4lo.asm Call with: ES:[DI] = address of first element of array to sort CX = number of array elements Returns: nothing Uses: nothing; all registers and flags are saved Example: include asm.inc extrn sorti4hi:proc .data i4data dd 1500 dup(0) .code . ; program establishes data values . . mov ax,@data mov es,ax assume es:@data lea di,i4data mov cx,1500 call sorti4hi 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRTOI2: converts an ASCII string to equivalent integer value STRNTOI2: converts n bytes of an ASCII string to equivalent integer value strtoi2 and strntoi2 ignore leading blanks and tabs, then read the string until a non-numeric character is read. strntoi2 reads a maximum of CX characters or until a non-numeric character is read, whichever comes first. Source: strtoi2.asm STRTOI4: converts an ASCII string to a long integer value STRNTOI4: converts n bytes of an ASCII string to a long integer value similar to strtoi2 and strntoi2, but returning a long integer value in DX:AX. Source: strtoi4.asm Call with: DS:[SI] = address of string strntoi2/strntoi4 only: CX = number of bytes to read Returns: AX = integer value, or DX:AX = long integer value strtoix: DS:[SI] points to character past terminating byte strntoix: if CX = 0, DS:[SI] points to next character if CX <> 0, DS:[SI] points to character past terminating byte BL = error code bit 0 if set = CR read before reading any numeric characters bit 1 if set = CR was the terminating character bit 6 if set = overflow; result in DX:AX is unusable bit 7 if set = result is unsigned; result is unusable if the value represented by the string was negative Uses: AX, BX, CX, SI, flags Example: lea si,long_integer ; near address of ASCII string mov cx,7 ; 7-byte field call strntoi2 ; return result as an integer in AX 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRCAT: catenates (combines) two ASCIIZ strings Source: strcat.asm (strdup.asm, strlen.asm, heap.asm) Call with: DS:[SI] = address of first string DS:[BX] = address of second string assumes DS:@data Returns: if CF = 0, DS:[BX] = address of combined ASCIIZ string if CF = 1, insufficient memory available in near heap Note: you must initialize the near heap with HINIT before using STRCAT. See STARTUP.ASM. Uses: BX, CX, CF Example: include asm.inc extrn strcat:proc .data string0 db 'this string goes first',0 string1 db ' this one is added at the end of the first',0 .code ; program fragment assumes DS:@data . . . lea si,string0 ; address of first string lea bx,string1 ; address of second string call strcat ; result returned at DS:[BX] jc heap_is_full ; original strings are undisturbed 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRCHR: search an ASCIIZ string for a specified character STRNCHR: search n bytes of an ASCII string for a specified character Source: strchr.asm (strlen.asm) Call with: DS:[BX] = pointer to ASCIIZ string AL = character to find CX = number of bytes to search (strnchr only) Returns: CX = string length if CF = 0, AX is the offset from DS:[BX] to matching character in the source string if CF = 1, no matching character found Uses: CX, AX, CF Example on next page ; use STRNCHR to determine if a key pressed was a legal key include asm.inc extrn strnchr:proc, getkey:proc, toupper:proc .data valid_string db 'ABC123',27 ; keys 1,2,3,A,B,C and Esc valid_len equ $-valid_string ; number of valid keys dispatch_table label word dw akey, bkey, ckey, onekey, twokey, threekey, esckey .code ; program fragment assumes DS:@data . . . get_another: lea bx,valid_string ; DS:[BX] points to a string of valid keys call getkey ; keycode returned in AX shr ah,1 ; test for extended keycode jc get_another ; I'm not interested in extended keycodes today call toupper ; convert keycode to upper case mov cx,valid_len call strnchr jc get_another ; CF = 1 if key pressed is not among the ; keys in the validation string mov bx,ax shl bx,1 ; convert byte offset to word offset jmp dispatch_table[bx] akey: . . . bkey: . . . ckey: . . . ; etc 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRCPY: copy an ASCIIZ string to existing buffer Source: strcpy.asm (strlen.asm, strncpy.asm) Call with: ES:[BX] pointing to ASCIIZ string DS:[SI] pointing to destination buffer STRCPY assumes that the buffer is long enough to hold the entire string. The string's terminating NUL byte is not copied to the buffer. Returns: CX = string length Uses: CX Example: include asm.inc extrn strcpy:proc .fardata fstring db 'a far string',0 .data string_buffer db 128 dup (?) .code ; code fragment assumes DS:@data . . . ; copy far string to DGROUP for convenient manipulation mov ax,@fardata mov es,ax assume es:@fardata mov bx,offset @fardata:fstring mov si,offset @data:string_buffer call strcpy 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRNCPY: copy CX bytes to an existing buffer Source: strncpy.asm Call with: ES:[BX] pointing to ASCII string DS:[SI] pointing to destination buffer CX = number of bytes to copy STRNCPY assumes that the buffer is long enough to hold the entire string Returns: nothing Uses: nothing; all registers and flags are saved Example: ; I want to copy a command line parameter to DGROUP include asm.inc extrn getcmd:proc extrn strncpy:proc .data extrn pspseg:word ; PSP segment address was saved by STARTUP string_buffer db 128 dup (?) .code ; code fragment assumes DS:@data . . . mov es,pspseg xor ax,ax ; first command line parameter call getcmd ; returns parameter at ES:[BX], length as CX jcxz no_parameters lea si,string_buffer call strncpy ; make it zero-terminated add si,cx mov byte ptr [si],0 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRINS: inserts string1 in string0 at specified offset. Creates new string in near heap; first part of new string is n bytes of string0; middle of new string is string1; end of new string is remainder of string0. Source: strins.asm (strlen.asm, heap.asm) Call with: DS:[SI] pointing to string0 DS:[BX] pointing to string1 AX = offset in string0 to insert string1 (0 >= AX >= 32767) Assumes DS:@data Returns: if CF = 1, insufficient memory in hear heap if CF = 0, DS:[BX] points to new string Note: you must initialize the near heap with HINIT before using STRINS. See STARTUP.ASM. Uses: BX, CF Example: include asm.inc extrn strins:proc .data string0 db '1234567890',0 string1 db 'abcdefghij',0 .code . . . mov ax,@data mov ds,ax ; dgroup assume ds:@data ; tell MASM about it lea si,string0 ; address of first string lea bx,string1 ; address of second string mov ax,3 ; string1 inserted after '123' call strins ; result returned at DS:[BX] jc heap_is_full ; original strings are undisturbed 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRDUP: duplicates a string at ES:[BX] Source: strdup.asm (strlen.asm, heap.asm) STRNDUP: duplicates n bytes of a string at ES:[BX] Source: strndup (strdup.asm, heap.asm) Call with: ES:[BX] = address of source string assumes DS:@data (strndup) CX = number of bytes to duplicate String copied to near heap Source string need not be in same segment as heap strdup requires an ASCIIZ string; strndup duplicates CX characters at ES:[BX] whether zero-terminated or not. The duplicate created by strdup or strndup will be an ASCIIZ string. Returns: if CF = 0, DS:[BX] = address of string copy CX = string length if CF = 1, insufficient memory in near heap Note: you must initialize the near heap with HINIT before using STRDUP. See STARTUP.ASM. Uses: BX, CX, CF; all other flags and registers are saved Example: mov ax,@data mov ds,ax mov es,ax ; in this case, the source string ; is in the data segment lea bx,source ; ES:[BX] = source address call strdup jc oops ; not enough memory if CF = 1 ; otherwise, DS:[BX] = address ; of string copy 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRIPCHR: remove all occurances of a character from an ASCIIZ string. Source: stripchr.asm (strlen.asm) Call with: DS:[BX] = string address AL = character to remove from the string Returns: CX = new string length Uses: CX Example: lea bx,string ; DS:[BX] -> string mov al,'$' ; remove "$" character from string call stripchr 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRLEN: finds length of an ASCIIZ string Source: strlen.asm Call with: DS:[BX] = address of the string Returns: CX = length of string excluding the terminating NUL Uses: CX Example: lea bx,string call strlen 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRLWR: changes upper-case characters in a string to lower case Source: strlwr.asm STRNLWR: changes n bytes of a string to lower case Source: strnlwr.asm Call with: DS:[BX] = address of an ASCIIZ string CX = number of bytes (strnlwr only) Returns: nothing Uses: nothing Example: lea bx,string call strlwr 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRRCHR: find the last byte in a string matching AL STRNRCHR: find the last byte in n bytes matching AL Source: strrchr.asm (strlen.asm) Call with: DS:[BX] pointing to the first character of the string AL = byte to find (strnrchr only) CX = number of bytes to search Returns: if CF = 1, no match if CF = 0, AX = offset from DS:[BX] of the last matching byte Uses: AX, CF; all other flags and registers are saved Example: .data string db 'my old computer was a real slug',0 .code . . . mov ax,@data mov ds,ax assume ds:@data mov al,'w' ; look for the lower-case "w" lea bx,string call strrchr jc oops ; cut outta here if not in the string ; else go on 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRREV: reverses all characters in a string STRNREV: reverses n characters in a string Source: strrev.asm (strlen.asm) Call with: DS:[BX] pointing to the first character of the string CX = number of bytes in string to reverse (strnrev only) Returns: CX = string length Uses: CX; all other registers and flags saved Example: lea bx,string ; DS:[BX] points to ASCIIZ string call strrev ; also returns CX = string length 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRSPACE: creates an ASCIIZ string filled with the space character, terminated with NUL Source: strspace.asm (heap.asm) Call with: AX = string length (not including terminating NUL) Assumes DS:@data Returns: if CF = 1, insufficient memory in near heap if CF = 0, DS:[BX] points to the new string CX = string length (should be same as AX) Note: you must initialize the near heap with HINIT before using STRSPACE. See STARTUP.ASM. Uses: CX, BX, CF Example: mov ax,14 ; make a new string 14 characters long call strspace jc oops ; not enough memory if CF = 1 mov string14,bx ; else save pointer to string 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRSET: sets all bytes of an ASCIIZ string to a specified character STRNSET: sets n bytes of an ASCIIZ string to a specified character Source: strset.asm (strlen.asm) Call with: DS:[BX] pointing to a valid ASCIIZ string AL = character CX = number of bytes to set (strnset only) Returns: CX = string length Uses: CX Example: lea bx,string ; DS:[BX] points to an ASCIIZ string mov al,'*' call strset 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRSTR: finds the first match with a target string in a source string case sensetive Source: strstr.asm ($strstr.asm, strlen.asm) STRISTR: finds the first match with a target string in a source string case insensetive Source: stristr.asm (strstr.asm, strdup.asm, upcase.asm, heap.asm) STRRSTR: finds the last match with a target string in a source string case sensetive Source: strrstr.asm (strrev.asm, $strstr.asm) Call with: ES:[DI] pointing to source string, DS:[SI] pointing to target string. STRISTR assumes DS:@data Returns: if CF = 0, AX = offset of target in source string. if CF = 1, no match Note: you must initialize the near heap with HINIT before using STRISTR. See STARTUP.ASM. Uses: AX, CF; all other flags and registers are saved Example: mov ax,@fardata mov es,ax assume es:@fardata ; source string is in far data area mov ax,@data mov ds,ax assume ds:@data lea di,string ; source = 'monday',0 lea si,substring ; target = 'day',0 call strstr ; in this example, strstr returns ax = 3 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� STRUPR: changes lower-case characters in an ASCIIZ string to upper case Source: strupr.asm STRNUPR: changes lower-case characters in an n-length string to upper case Source: strnupr.asm Call with: DS:[BX] pointing to string (strnupr only) CX = number of bytes in string Returns: nothing Uses: nothing Example: mov bx,offset string mov cx,bytes call strnupr 같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같같� SWAPB: swaps AX bytes at DS:[SI] with the same number at ES:[DI] Source: swapb.asm Call with: DS:[SI] pointing to one of the data areas, ES:[DI] pointing to the other AX = number of bytes to swap Returns: nothing Uses: nothing; all registers and flags are saved Example: include asm.inc extrn swapb:proc .data string1 db 'this is string 1',0 string2 db 'this is string 2',0 strings dw string1, string2 ; addresses of the strings ; this example will swap ; the string pointers .code public stringswap stringswap proc ; program fragment assumes DS:@data . . . lea si,strings push ds pop es ; ES = DS mov di,si mov ax,2 ; each string pointer is 2 bytes add di,ax ; point to 2nd pointer call swapb