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Text File | 1985-11-25 | 31.4 KB | 723 lines

Batch File Sorts (PC Magazine Vol 3 No 8 May 1, 1984 User-to-User) In DOS 2.x it's easy to use batch files and filters to list your files alphabetically by filename, filename extension, or by the size of the file. To do this, make sure your SORT.EXE file is on the disk you are sorting, and create a batch file called SDIR.BAT: A>COPY CON:SDIR.BAT <Enter> DIR %1: |SORT /+%2>%3 Then hit the F6 key, and then the Enter key. (The vertical bar character (|) before the word SORT is the DOS "piping" symbol.) In this batch file, %1 designates the drive containing the directory to be sorted, %2 stands for the column number of the directory to be sorted, and %3 is the filename which it is to be saved under. Note that since there is a colon after %1, you won't have to enter a colon when you tell SDIR.BAT which disk to sort. To sort drive A alphabetically (using the first column), you would type: A>SDIR A 1 A:ASRT.DIR then hit the Enter key and you'll see on the screen: A>DIR A:|SORT /+1>A:ASRT.DIR For alphabetization of the FILENAME EXTENSION, type in 9 instead of 1. Type: A>SDIR A 9 A:FXSRT.DIR then hit the Enter key. For the DIR to be listed by the size of the files, replace the 9 with 13: A>SDIR A 13 A:SZSRT.DIR and you'll get the same results as above but a different sorting of the directory. You can also get a reverse order listing of the directory by typing /R after the column number: A>SDIR A 13/R A:RSRT.DIR and hitting the Enter key. Once you've created these sorted directory files, to use them just type the DOS TYPE command. To view the initial alphabetical listing described above, for instance, type: A>TYPE ASRT.DIR then hit the Enter key and you'll see all the files on your disk rearranged alphabetically by filename. It's probably best to have three batch files on your disk: SDIR.BAT to create sorted files, PSDIR.BAT to create them and print them out on your printer, and SSDIR.BAT to create them and print them on your screen. For PSDIR.BAT type: A>COPY CON:PSDIR.BAT <Enter> DIR %1:|SORT/+%2>%3 <Enter> COPY %3 LPT1: <F6><Enter> For SSDIR.BAT, type: A>COPY CON:SSDIR.BAT <Enter> DIR %1:|SORT /+%2>%3 <Enter> COPY %3 CON: <F6><Enter> ----------------------------------------------------------------- Assembling a Port Switch (PC Magazine Vol 3 No 18 Sept 18, 1984 User-to-User) The following .COM program written through DEBUG's Assemble command in DOS 2.0 will run two printers for use with dBASE II. The file is named PSWITCH.COM. A>DEBUG -NPSWITCH.COM -A 1363:0100 MOV AX,0040 1363:0103 MOV DS,AX 1363:0105 MOV SI,0008 1363:0108 MOV AX,[SI] 1363:010A XCHG [SI+02],AX 1363:010D MOV [SI],AX 1363:010F MOV AX,004C 1363:0112 INT 21 1363:0114 -RCX 0000: 0014 -W Writing 14 bytes -Q A> ----------------------------------------------------------------- Sloppy Floppies (PC Magazine March 20, 1984 User-to-User) This procedure that will sort and keep track of files on floppy disks and let you locate any file in seconds. You need DOS 2.x and a word processor, i.e., WordStar. First number all your disks on their labels. DOS 2.x allows redirection of I/O, which will put the directories of each disk into individual files. To do this, get into DOS, put a blank, formatted disk into drive B:, put your disk #1 into drive A:, and at the DOS prompt A> type: DIR>B:DISK1 <Enter> Then put disk #2 in, and type the same thing; disk #3, etc. When you're all done, you'll have a lot of directories on drive B: named DISK1, DISK2, DISK3, etc. Append them into one master file by typing: COPY B:*. DIRECTRY This will merge all of the individual directory files into one master file called DIRECTRY. All you have to do now is go into that master DIRECTRY file with WordStar, number the individual directories sequentially, and clean them up if you don't want to see the "bytes free" messages or the "Volume in drive A has no label" messages. To find what disk a file is on, use WordStar's string search command (^QF) to hunt for the filename. Scroll up through the individual listing, once WordStar has found a match, to see what the number of the disk is. You can find all sorts of uses for this. For instance, you could see if copies of a file are on more than one disk, or look at every file that you created or modified last Tuesday, etc. When you change the contents of any of the files on one of the disks listed in your master directory, you have to redirect the changed disk's directory into a temporary file, then get into the master directory and delete the old listing and read in the temporary file. You can do this is WordStar with block moves -- ^KB^KK^KY to remove the old directory, then ^KR to read in the new one. You might also be able to use DOS FIND and SORT filter commands for this, but if you do so, you'll have to use your word processor to add the number of the disk to each line in each of your directory listings. ----------------------------------------------------------------- Using DOS 2.0 To Organize Your Diskettes (PC Age May 1983 by Willard A. Brown) Keeping track of the contents of dozens of diskettes when their contents are frequently altered can be a problem. Here is a process for making order out of chaos by creating a catalog of the contents of a group of disks: 1. Format a disk give a volume name indicating its use: a catalog of disks and their contents. 2. Place the disk that is to be cataloged in drive A. 3. Type the following: DIR|SORT>B:DISK1.DRA (If the disk being cataloged has been assigned a name, use that name instead of DISK 1.) 4. Place the next disk in drive A. 5. Type the same as above, but change the filename. 6. Continue until 10 disks have been cataloged, then start using an extension of DRB instead of DRA and repeat for the next 10 disks. The reason for this has to do with the PRINT command (see below). 7. Copy to your catalog disk in drive B the following files from your DOS disk: CHKDSK.COM, FIND.EXE, MORE.COM, PRINT.COM, SORT.EXE, and TREE.COM. Next you will want to make several batch files for future convenience in searching through your catalog and making printed copies. The code listing below shows a sample. After completion of this task, if you type DISPLAY, you will find on your screen a sorted page full of the names of the files that have been created. Pressing the space bar will cause display of the next full page. Of if you type SEARCH followed by a string of characters you will have a display of those disk names that have filenames that include the specified string of characters. The PRINT command can store pointers for no more than 10 files. For this reason you store groups of 10 with extensions of DRA, DRB, DRC, etc. in the procedures above. Using this strategy you can request printing of the entire stream of directories in a reasonably efficient way. Thirty disks would only require three command lines. The reason that a batch file is suggested for the first group is that it serves as a reminder of the form that the command line should take. - - - - - B>COPY CON:DISPLAY.BAT DIR|SORT|MORE B>COPY CON:SEARCH.BAT FIND "%1" DISK1.DRA DISK2.DRA DISK3.DRA FIND "%1" DISK6.DRA DISK7.DRA FIND "%1" DISK11.DRB DISK12.DRB B>COPY CON:PRINTA.BAT PRINT *.DRA ----------------------------------------------------------------- Bug Hung (PC Magazine Vol 4 No 2 Jan 22, 1985 User-to-User) 1. If your default drive is A: and you are trying to rename a file in drive B: with the BASIC NAME command, you get a "Rename across disks" error message. The solution is to not use the format given in the BASIC manual. Instead use "NAME filespec AS filespec." 2. Advanced programmers using IBM's ASM/MASM Assembler may be puzzled by a mysterious "?End of file encountered on input file" error message that appears on start-up. It's not in IBM's manuals. All it means is that you probably answered the start-up prompts with a complete filespec instead of just a filename. All the assembler wants is "[d:]filename". You probably entered "[d:] filename.ext". 3. If CHKDSK reports one more hidden file than you think you should have, you probably just formatted the disk with the /V switch. CHKDSK reports the VOLUME ID label as a hidden file. 4. Do your batch files end with a double prompt A> A>? You can avoid this by typing the EOF marker (Ctrl-Z or function key F6) on the same line as the last command instead of on the next line. A blank space typed before the marker is optional. 5. Are you annoyed by the REMs that clutter up your display when you want to make a REMark in a batch file with ECHO ON? Try using a period (.) instead. It means the same as REM, but it yields a much neater display. There is also another use for the period with ECHO OFF. To skip lines between commands, use an ECHO . command wherever you want a blank line. The line displayed will be blank except for a single period in the first position. 6. If you're using your word processor to write batch files, the EOF marker is usually not available from the F6 key. Use a Ctrl-Z key combination instead. Your screen will show a "right arrow", the ASCII symbol for Ctrl-Z. 7. When using a RAMdisk, you must have a complete operating system in place if you want to invoke DOS commands from the RAMdisk. Use SYS d: and COPY COMMAND.COM d: to load IBMBIO.COM, IBMBIO.COM, and COMMAND.COM into the first three files on your RAMdisk. Make sure that they are the first three files and that IBMBIO.COM resides in contiguous sectors. The easiest way to do this is to start with a completely empty RAMdisk. Editor's Notes: (1) When renaming files on one disk from another, be sure and play it safe by putting the drive at the beginning of each, for example, name B:TEST.BAS as B:RETEST.BAS. While it's true that the BASIC manual is confusing, it makes one good point -- filenames don't default to a BAS extension; you have to add it if you want it. (6) It's generally safe to end a line with Ctrl-Z (F6 in DOS), but there are times when a line has to end in a carriage return. For instance, if you're typing ANSI magic, you have to hit the carriage return before the Ctrl-Z. But normal batch files don't usually need the extra carriage return. (7) DOS 3.0 doesn't let you use a period (.) instead of a REM. If you want to save trouble, you can use the COMMAND C:\ to move COMMAND.COM, but it's not necessary to schlep the hidden files on RAMdisk. ----------------------------------------------------------------- Tidy Lister (PC Magazine Vol 4 No 2 Jan 22, 1985 User-to-User) If you are putting up with "untidy" listings of long BASIC programs, help files and the like, you can modify the DOS 2.x MORE filter to pause after a full page rather than a 24-line screenful. Alter MORE to pause every 55 lines by: 1. Make a copy of MORE.COM under another name -- PORE.COM. 2. With DEBUG.COM and PORE.COM in the default drive, enter: A>DEBUG PORE.COM - D - E0118 - xxxx:0118 19.37 - W - Q (Note: Check for the value "19" which should appear at offset :0118, the byte at the right of the long line, and ignore the numbers that replace xxxx.) Now when you need a listing of a BASIC program (saved in ASCII) or any ASCII file from DOS, enter: TYPE FILENAME|PORE>LPT1: Use the correct device name (if different) in place of LPT1:. After listing 54 lines of the file, the printer pauses. With a quick Off-Line/Form-Feed/On-Line sequence a a press of any key, the next page is off and running. Editor's Note: You can also create a batch file, called PMOR.BAT, that automatically does this job: A>COPY CON:PMOR.BAT TYPE %1|PORE>LPT1: Then, to type a file with the new PORE pauses in it while in DOS, just enter PMOR <filename>. Also, to avoid having the phrase "--more--" appear on your printouts, while you're in DEBUG, add the following line just before you write (by hitting W): -F 1F1 1FA 20 This replaces the "--more--" message with blank spaces. ----------------------------------------------------------------- Poor Man's MODE (PC Magazine Vol 4 No 15 July 23, 1985 User-to-User) While the DOS MODE command performs a variety of I/O functions, many readers probably use it only to select video modes. It's possible to bypass MODE.COM and do this directly by using the SCREEN.COM program below, which speeds things up and saves 5K of space on disk. Once you've entered the program using DEBUG, use the command SCREEN n, substituting a number from 0 to 3 in space of n. Here are the new SCREEN n values along with their old MODE n equivalents: New SCREEN n Old MODE.COM n 0 BW40 (or 40) 1 CO40 2 BW80 (or 80) 3 CO80 Editor's Note: This does the job, but MODE.COM cones in handy elsewhere and at 5K isn't a space hog, especially on a hard disk. But if you're tight for space on a floppy, or if you want to give away or sell a disk and don't want to put IBM's copyrighted MODE.COM on it, this is for you. - - - - - A>debug -n screen.com -a xxxx:0100 xor ax,ax xxxx:0102 mov bx,0081 xxxx:0105 cmp byte ptr [bx],20 xxxx:0108 jnz 010d xxxx:010A inc bx xxxx:010B jmp 0105 xxxx:010D mov al,[bx] xxxx:010F cmp al,33 xxxx:0111 ja 0117 xxxx:0113 cmp al,2f xxxx:0115 ja 0119 xxxx:0117 mov al,33 xxxx:0119 sub al,30 xxxx:011B int 10 xxxx:011D int 20 xxxx:011F -rcx CX 0000 :lf -w Writing 001F bytes -q ----------------------------------------------------------------- Screen Blanker (PC Magazine Vol 4 No 15 July 23, 1985 User-to-User) For users who leave their monitors on all night to use the CTTY remote control, the program below will blank their screens as recommended in "Remote Access with CTTY" (Vol 4 No 3). Enter the program with DEBUG. To run the program, simply type BLANK at the DOS prompt. To return from the blank screen, use the DOS MODE command or change the byte at &h108 from 00 to 07. - - - - - A>debug -a 100 xxxx:0100 mov dx,1950 xxxx:0103 mov cx,0000 xxxx:0106 mov ax,0600 xxxx:0109 mov bh,00 xxxx:010B int 10 xxxx:010D mov al,00 xxxx:010F mov dx,03d9 xxxx:0112 out dx,al xxxx:0113 int 20 xxxx:0115 -rcx cx 0000 :114 -n BLANK.COM -w Writing 0114 bytes -q NOTE: To create UNBLANK.COM, substitute MOV BH,07 for the line MOV BH,00 and enter MOV AL,# instead of MOV AL,00 -- substituting the hex number of your border clor (3=cyan, 2=green, etc.) for the #. Also, name it UNBLANK.COM. ----------------------------------------------------------------- Beyond DOS COMPare (PC Magazine Vol 4 No 16 Aug 6, 1985 User-to-User) The DOS compare files command (COMP) compares two files until it finds 10 differences, then stops. You may want to compare two files even though the number of differences exceeds this limit. For DOS 2.x, use DEBUG to change the limit to any number of comparisons you'd like: A>DEBUG COMP.COM -e 39a nn -e 809 "xx" -w Writing 09E6 bytes -q To change the number to 14, for example, replace the nn with 0E (the hex notation for 14) and the "xx" to "14". For DOS 3.x, substitute 879 for 39a and b51 for 809. This patch will let you change COMP to continue file comparisons without any limit on the number of byte-by-byte differences COMP finds for DOS 2.x: A>DEBUG COMP.COM -e 39b 90 90 -w Writing 09E6 bytes -q For DOS 3.x, use 87a for 39b. Editor's Note: This DOS 2.x trick works, but it doesn't handle the annoying problem where, if there is just one extra byte at the beginning of one file being compared, COMP gets confused and the whole process becomes meaningless. ----------------------------------------------------------------- Cursor Toggling (PC Magazine Vol 4 No 22 October 29, 1985 User-to-User) CURSON.COM, written for a color display, turns the cursor back on if it disappears when exiting from a program. To adapt it to work on a monochrome display, change the 0607 in the first MOV instruction to 0C0D. Also, if you want to turn the cursor off, change the same instruction to 0F00. A>DEBUG CURSON.COM File not found -A xxxx:0100 MOV CX,0607 xxxx:0103 MOV AH,01 xxxx:0105 INT 10 xxxx:0107 INT 20 xxxx:0109 -RCX CX 0000 :9 -W Writing 0009 bytes -Q ----------------------------------------------------------------- Cursoring a Blue Streak (PC Magazine Vol 4 No 25 Dec 10, 1985 PC Tutor) The size of the cursor on the PC can be controlled by ports on the 6845 video controller chip. It's easier to use the BIOS Interrupt 10h function call 01h, however. Use DEBUG to create the CURSOR.COM program below that will let you experiment with different cursor sizes. The program takes two arguments (each a 2-digit hex number) to specify the top scan line and the bottom scan line of the cursor. You can start by entering the following commands, depending on whether you have a monochrome or color/graphics display: Monochrome Normal: CURSOR 0B 0C Monochrome Box : CURSOR 00 0C Color Normal : CURSOR 06 07 Color Box : CURSOR 00 07 Using CURSOR.COM to experiment with cursor size is better than using the BASIC LOCATE statement because you can go beyond 1F hex (or 31 decimal) in the arguments. You may notice through experimentation that the blink is slowed down somewhat by values of 6x (for instance, CURSOR 66 67), but it cannot be turned off entirely. Whether other programs will destroy your settings depends on the program. Some do; some don't. For programs that use a nonblinking cursor, you're seeing a hardware-generated cursor. Programs can hide the read hardware cursor and then create their own "cursor" by writing the characters to the display with a reverse-video attribute. Mimicking this process in a memory-resident utility is not entirely successful. BIOS Interrupt 10h calls can be intercepted to substitute a reverse-video screen attribute for the blinking cursor, but this only worked at the DOS-command level. It was an absolute mess with some other programs. For instance, WordStar 3.30 uses the BIOS services to set the cursor position, but it uses direct memory to write to the screen and scroll it. This results in multiple copies of a "cursor" appearing all over the screen. A>DEBUG -A xxxx:0100 MOV AX,[005D] xxxx:0103 CALL 0116 xxxx:0106 MOV CH,AL xxxx:0108 MOV AX,[006D] xxxx:010B CALL 0116 xxxx:010E MOV CL,AL xxxx:0110 MOV AH,01 xxxx:0112 INT 10 xxxx:0114 INT 20 xxxx:0116 CALL 0125 xxxx:0119 XCHG AL,AH xxxx:011B CALL 0125 xxxx:011E MOV CL,04 xxxx:0120 SHL AH,CL xxxx:0122 ADD AL,AH xxxx:0124 RET xxxx:0125 OR AL,20 xxxx:0127 SUB AL,57 xxxx:0129 JNB 012D xxxx:012B ADD AL,27 xxxx:012D RET xxxx:012E -N CURSOR.COM -R CX CX 0000 :002E -W Writing 002E bytes -Q ----------------------------------------------------------------- Behind the Eight Ball with DEL (PC Magazine Vol 4 No 22 October 29, 1985 User-to-User) Here's an easy, new and undocumented feat of prestidigitation. A mere slip of the finger, and much of your current subdirectory or floppy disappears like magic! Say you've got a bunch of files whose names don't have extensions, like MOE, LARRY and JOE. You've also got some with the .BAT extension: MOE.BAK, LARRY.BAK and CURLY.BAK. May as well get rid of those useless backups. Nothing to it. You simply type: erase *.bak (or del *.bak). Except that after you hit the asterisk over the 8, you accidentally let go of the Shift an instant too late. What you type instead, since the > sign is over the period, is: erase *>bak (or del *>bak). You hit the Enter key before you catch the error. And when you look at the directory, you discover the .BAK files are still there. Missing are all of your files whose names lack extensions. MOE, LARRY and CURLY are gone, and so are PETER, PAUL and MARY. You may not see it in the directory, but you now have a file called BAK whose length is zero. Agony! An immediate trip to the undelete utility. It's likely to be a long session. Seeing the > sign, DOS thought you were trying to redirect the output of the ERASE command into a file called BAK; the output of the ERASE command is nothing at all. Of course, the lone asterisk meant you wanted to erase all files whose names lack extensions. DOS was kind enough to oblige. Moral: when using the ERASE or DEL command, avoid the Shift keys. Use the asterisk under PrtSc instead of the one over the 8. Or automate things; create a batch file with the single line: del *.bak, and call it DELBAK.BAT. Then you type in DELBAK and you'll never find yourself behind the eight ball. Editor's Note: Using the PrtSc asterisk introduces another headache. If you happen to be leaning on a Shift when you hit this key, you either get a printed page full of junk if your printer is on-line, or a long hang if it's not. The batch file is the best solution, and add three lines at the beginning: echo off echo Ready to del .BAK files pause This reminds you of what you're doing and gives you one more chance to Ctrl-Break out before a valuable backup file vanishes. ----------------------------------------------------------------- Global FIND (PC Magazine Vol 4 No 6 March 19, 1985 User-to-User) The only problem with the DOS 2.x command FIND is that you cannot use global filename characters in specifying the names of the files you want searched. Sometimes you want to search all the files on a disk for a particular string, and entering all the filenames is a bother. One way to avoid entering all the filenames is to use the FOR command. If FIND.EXE is in drive A:, and the disk you want to search is in B:, the following command, which must be executed as part of a batch file, will search all the files on B: for the string "your generous offer": FOR %%F IN (B:*.*) DO FIND "your generous offer" IN %%F This command executes quickly, but it can go much faster if the files being searched are on a RAMdisk. Also, since FIND is an external command, it is loaded every time the command is executed so FIND should be on a RAMdisk. There is one problem to be solved. When FIND examines itself it sends the PC into never-never land and has to be rebooted. So FIND should be in a different subdirectory. As a remedy, create a subdirectory named \FINDSD and copy FIND.EXE into it. Then make the root directory the default directory, copy this batch file into it, and execute the batch file: ECHO OFF PATH \FINDSD FOR %%F IN (*.*) DO FIND "your generous offer" IN %%F ----------------------------------------------------------------- FIND Unquoter (PC Magazine Vol 4 No 13 June 25,1985 User-to-User) As a frequent user of the DOS FIND filter, I grew tired of having to enclose each string I was searching for inside quotation marks. I figured out how to fix FIND.EXE so that quotes are not necessary (see below). The drawback is that his new version of FIND can't search for strings containing spaces. I named this utility after the UNIX command FGREP. - - - - - Instructions for changing DOS 3.0 FIND.EXE: A>copy find.exe fgrep 1 File(s) copied A>debug fgrep -e 3cc xxxx:03CC 75.4e 0A.90 -e 3e9 xxxx:03E9 22.20 -e 3ec xxxx:03EC AC.90 3C.90 22.90 74.90 xxxx:03F0 0F.90 4E.90 -w Writing 18DB bytes -q A>rename fgrep fgrep.exe ----------------------------------------------------------------- Random File SORTs (PC Magazine Vol 4 No 10 May 14, 1985 User-to-User) The SORT filer command in DOS 2.1 does not work satisfactorily. The program is supposed to read data from the standard input device, sort it and write the data to the standard output device. It can sort data in alphabetical order or in reverse alphabetical order and can begin the sort on a specified column. The problem is that a programmer can specify whatever record length he wants when he loads BASIC. Unfortunately, the SORT filter does not know the length of the records in a random file since the operation is conducted in DOS, not BASIC. There is a way around this problem. To tell the SORT filter where each record ends, you must add a carriage return and then a line feed at the end of each record. This is easily handled by following these steps: 1. OPEN the file as usual. 2. FIELD the file, adding as the last two variables: 1 AS CR$, 1 AS FL$ 3. LSET as usual with the following two last statements LSET CR$=CHR$(13):LSET LF$=CHR$(10) Now when the SORT filter begins, it will automatically know where each record ends, and the command will work properly. Additionally, if you want to examine the actual file using the DOS TYPE command, you will notice that each record will begin at the left edge of the screen, which makes examining the file much easier. Finally, be sure to allow for the extra bytes when OPENing the file. Editor's Note: SORT needs carriage returns at the end of each record to work properly, and this inserts them properly. But sorting random length files can pose problems, for instance, when you're sorting on a specified column that isn't there. In any event, it would be simple to write a short BASIC program that reads an existing random file, adds carriage returns, and writes the data to a new file with slightly longer FIELDs so the records could be sorted properly. ----------------------------------------------------------------- Five Easy Patches (PC Magazine Vol 4 No 24 Nov 26, 1985 User-to-User) Even DOS 3.1 COMMAND.COM has deficiencies. The first deficiency is that whoever wrote COMMAND.COM didn't know how many lines are on a standard video display, since the CLS command will clear 26 lines rather than the standard 25. While this may not appear to be a problem, if you run a program that uses the PC's extra video pages, you may find the first line of an extra page mysteriously erased. The reason for the error is probably that the video-scroll function in BIOS is based on zero-relative values, so the existing COMMAND.COM value of 25 actually clears lines 1 through 25, plus line 0. To fix this bug, make sure DEBUG and DOS 3.1 COMMAND.COM are on your disk and type: DEBUG COMMAND.COM E 263B 18 W Q The second problem lies in the DOS 3.1 ECHO command. While undocumented, it is an accepted fact that in a batch file an ECHO command followed immediately by two spaces will generate a blank line. This works on earlier versions of DOS, but not 3.1. Instead of displaying a blank line, DOS will return the current status of ECHO. Since most batch files start by turning ECHO off, instead of inserting clean blank lines, this problem clutters your screen with a lot of "ECHO is off" messages. To fix COMMAND.COM so ECHO and two spaces will produce a blank line, make sure DEBUG and DOS 3.1 COMMAND.COM are on your disk and type: DEBUG COMMAND.COM E 3878 83 E 3879 F9 E 387A 02 E 387B 72 W Q Problem three is that COMMAND.COM normally defaults to ECHO ON, forcing most users to turn it off in the first line of all their batch files. Apart from being a nuisance, this puts an ECHO OFF line on the screen. COMMAND.COM handles this default separately for AUTOEXEC.BAT and for all other batch files. To turn the default to OFF in both cases, make sure DEBUG and DOS 3.1 COMMAND.COM are on your disk and type: DEBUG COMMAND.COM E 105B 2 E 1967 0 W Q The fourth and fifth problems are that DOS won't simply print the date and time if you request it; instead it will first stop and ask you for the new date and time. You can of course just hit the Enter key to procede, but this makes it harder to date- and time-stamp your files. The way to get aroudn this is to create two new commands, DATER and TIMER, that bypass the request for new information and send control directly to the routines that print the date and time. COMMAND.COM contains a table of familiar words such as DIR, RENAME (and REN), ERASE (and DEL), etc., that it examines every time you enter a command. Fortunately for anyone wishing to play with the command table, three words on the list -- CHDIR, MKDIR and RMDIR -- are redundant, since every user in the world uses the shorter CD, MD and RD versions. This lets us use the space on the table for TIMER and DATER. The reason these new commands are five letters long is, of course, that they will replace existing five-letter commands. The DOS 3.1 COMMAND.COM command table begins at around 4CF4. Each entry on the table is made of four parts. The first is a byte that specifies how many characters are in the particular command. This is followed by the command itself. After the text of the command is a byte that seems to tell DOS whether the command needs an argument, may have an argument, or never requires an argument. Both TIMER and DATER don't need an argument, so this byte will be 0. The fourth part is the 2-byte address of the routine that COMMAND.COM will transfer control to. To change CHDIR to DATER, make sure DEBUG and DOS 3.1 COMMAND.COM are on your disk and type: DEBUG COMMAND.COM E 4D7D "DATER" E 4D82 0 E 4D83 2E E 4D84 26 W Q To change MKDIR to TIMER, type: DEBUG COMMAND.COM E 4D8C "TIMER" E 4D91 0 E 4D92 DF E 4D93 1E W Q While these patches are for DOS 3.1 only, some of them can be adapted to earlier versions of COMMAND.COM. Editor's Note: While some might argue that it's bad to use an undocumented feature like the ECHO+space+space above, once users learn about it they will incorporate it into their programs as if it were in the manual. Once you've made all the changes, you either have to reboot your system to install the patched COMMAND.COM, or invoke it as a secondary command processor by typing COMMAND. A nifty way to reboot automatically by using DEBUG is to create a file called RB that contains the five lines: rcs ffff rip 0000 g Make sure you include a carriage return at the end of each line. Then create a batch file called REBOOT.BAT that contains the one line: DEBUG < RB Be certain that DEBUG.COM is on your current directory, or that you PATH to it.