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---------------------------------------------------------------- BATCH FILES FOR EFFICIENCY - GETTING REAL WORK DONE ---------------------------------------------------------------- Batch files are one of the hidden treasures within your computer. Let's face it, learning and using DOS commands is a test of patience, memory and stamina. Batch files are the secret weapon which can boost your computer into the fast lane of work productivity. Batch files are small software programs which you can prepare in the space of only five or ten minutes which automate a variety of tasks and customize the computer to your work style. The bottom line is that batch files can preserve your sanity in the face of arcane, easily-forgotten DOS commands to provide you with a menu system for your hard drive, transfer and backup files, provide security, start other software programs, activate your printer and much more. Amazingly, batch files require that you become familiar with only eight commands in addition to the normal DOS commands. Working with batch files means you are programming in the most literal sense - let's take a tour of the small miracles called batch files . . . A batch file is little more than a list of DOS commands plus eight special batch commands. These commands are stored on your floppy or hard disk in an ordinary text file such as produced by your word processor or text editor. If you can type a letter to a friend, you can prepare a batch file! Several time-saving batch file examples which provide real work power to your everyday computer problems are presented at the end of this tutorial. We will also examine the eight basic batch file commands as well as the AUTOEXEC.BAT file which starts your computer each morning. In addition we will present some simple tricks for managing your printer with batch files. One way to think about a batch file is that it takes the place of your keyboard and issues commands one after another until it reaches a conclusion. Batch files operate line by line and are read directly from the disk which makes them a little slow, but nevertheless useful and flexible. You can eliminate repetitious keyboard tasks by using batch files. Let's look at a short batch file . . . Each line of a batch file contains one instruction or operation per line which the computer is to perform. Below is the listing of a simple batch file example. Don't worry about understanding it yet, simply note that each instruction is a DOS command on a separate line. The list in the left column is the actual batch file, while the explanation in the right column is NOT part of the batch file, only a helpful column of comments. EXAMPLE BATCH FILE EXPLANATION | | date date displayed time time displayed ver DOS version displayed dir a:/p directory of a: floppy displayed with a pause The primary use of batch files is to automate sequences or instructions which you use frequently. A batch file always has the extension BAT. A batch file might for instance be named MENU.BAT, CAR.BAT, INSTALL.BAT or MONEY.BAT. Each line in a batch file is a separate command and is performed in sequence as if you had typed in the command from your keyboard at the DOS prompt. In addition to the usual DOS commands, batch files can also contain additional special commands to provide truly sophisticated program structures which include decision branching and even repetitions of commands. In addition, batch files may have special parameters or inputs passed to them at the time you run the batch file from the DOS command line or prompt. A batch file is run or started by typing the file name without the extension. This of course also applies to files ending with file extensions EXE or COM as well as BAT. Example: A>hello (Then pressing enter or return key) This starts the file hello.bat hello.com or hello.exe Example: C>whoops (Then pressing enter or return key) This starts the file whoops.exe whoops.bat or whoops.com There are several ways to abort or terminate any batch file in progress. 1) Issue the break command which uses the two key combination CONTROL-BREAK (hold down the control or CTRL key then press the break key) or you can 2) Tap CTRL-SCROLL LOCK keys or 3) Tap CTRL-C keys. There are many ways to prepare a batch file, all of which use simple methods of text editing or word processing: 1) Use the DOS COPY CON (copy console) command. 2) Use the older EDLIN line editor available within older versions of DOS. 3) Use the newer DOS EDIT text editor available in DOS version 5.0 and 6.0. This is probably the most convenient. 4) Or use any word processor (e.g., Microsoft Word, Wordperfect, PC-Write) whose output has been set to ASCII or pure text output - many word processors use a "save as" file option to select pure ASCII output. See your word processor reference book index under ASCII file saving. Let's prepare a batch file: First make sure you have a formatted disk in your disk drive and DOS is displaying a DOS prompt such as A> or C>. We need a disk in order to save our batch file. We will be using the command COPY CON (copy data from the CONsole) command. We could also use any ASCII (plain english) text word processor (e.g., Wordperfect) or even EDLIN on your DOS disk. Note that you can use either upper or lower case to prepare batch files (capitals or small letters.) Using COPY CON is like using a small typewriter to prepare your batch file. Type the following list carefully at the DOS prompt: copy con blink.bat (press enter - cursor skips to new line) echo Hello there (press enter) ver (press enter) date (press enter) dir/p (press enter) ^Z (press F6 OR your can press control key AND Z key, then press enter) When done, you'll have prepared a batch file of DOS commands named blink.bat. Run the batch file by typing this at the DOS prompt: blink (then press enter key) Although using the COPY CON method method of preparing a batch file works, users of DOS 5.0 and 6.0 will find it more convenient to use the built in DOS "miniword processor" called EDIT. Just type the command EDIT <then press enter/return key> to load EDIT. Then use the convenient popdown menus within EDIT to create a file or load a file from the disk. WARNING! Be careful when preparing batch files since you will automatically overwrite and destroy any PREXISTING batch files of the same name! It may be better to make a backup copy of the existing batch file (or rename it temporarily with the REN command) and then proceed. A classic beginner mistake is to tinker with the crucial AUTOEXEC.BAT file without saving a backup copy first! If you destroy AUTOEXEC.BAT with your tinkering, you can replace it with your known good copy. More about AUTOEXEC.BAT later in this tutorial. We could also have named the batch file above hello.bat or info.bat rather than blink.bat by changing the first line we typed, but for simplicity we'll stick with blink.bat which does the following chores: Print "hello there" on the screen, then type the DOS version in use then display date and finally produce a directory listing with pause after each screenful. At this point the batch file ends and returns you to DOS. In the first line we use COPY CON as our small word processor to begin construction of the batch file named blink.bat. In the last line the ^Z means end of batch file preparation - exit back to DOS and save the file on disk. Another example batch file for you to try, let's call it F.BAT This is a reminder that F.BAT refers to formatting a disk: echo off copy con f.bat cls pause format b: echo all done Notice that here I have omitted the COPY CON command to start file preparation and the F6 to end file preparation. Use the COPY CON method described above if you wish or whatever word processing software is available to construct the file. This batch file (activated by typing f then enter) will clear the screen then prepare to format a blank disk in b: drive. NOTE: you MUST have FORMAT.COM, the DOS formatting utility, on the same disk as the batch file, f.bat - remember that format is an EXTERNAL command and f.bat will try to find FORMAT.COM. After the batch file has formatted the disk it prints "all done" on the screen. So instead of LOTS of keystrokes to format a disk, you just tap "F" then hit enter and the batch file runs. See how we are saving keystrokes - that's one of the purposes of a batch file! We will discuss the new ECHO command a little later in this tutorial. A reminder: Ctrl-Break or Ctrl-C key combination will halt any batch file operation if you wish. The next batch file might be used to backup word processing data files from your hard drive onto a floppy disk. Let's make an initial assumption that your word processing documents are stored on your hard drive in the subdirectory C:\DOC. You could name this backup batch file B.BAT and when you need to backup simply type B (then press enter) at the DOS prompt. We've omitted the copy con command at the top of the file and the ^Z at the end of the file since you already know how to start and end a batch file from previous examples. Note the new commands we are using: REM, ECHO and PAUSE which we will discuss shortly. ECHO OFF ECHO This batch file backs up DOCUMENT files to disk B: ECHO READY TO BACKUP. PAUSE COPY C:\DOC\*.* B: ECHO All done! The line which does most of the work is COPY C:\DOC\*.* B: which translates as "copy all files from C:\DOC subdirectory and transfer them to B: drive." One batch file can start or call another, but the original batch file cannot usually be returned to - you must continue on within the second batch file. For example, you could have one batch file start another batch file. If a batch file contains a typing or syntax error in any of its commands, the computer will stop execution at that point and return you to DOS which remembers which disk contains the batch file and the drive it was in. If you remove the original disk, DOS will ask you to replace it so it can finish executing the batch file. Batch files execute one step at a time from the disk and NOT from RAM memory. This disk-based nature of batch files make them a little slow, but they get the work done in reasonably short order for most people. Several books and power user tricks should also be mentioned regarding batch files before we move on . . . A superlative book on batch files you might wish to investigate is MOS-DOS Batch File programming by Ronny Richardson, 1988, Wincrest Books. You should also investigate the SEBFU (Scanlon Enterprises Batch File Utilities) software package which is a series of small batch file utilities which offer an improvement over the standalone DOS batch file programming language. SEBFU allows the user to produce subtle, powerful batch files and includes an excellent tutorial about using batch files for productivity. If you wish to try SEBFU, the shareware version, contact Scanlon Enterprises, 38354 17th ST E #C, Palmdale, CA 93550 Telephone (805) 272-4827. Include five dollars for shipping and handling. Special batch file COMPILER utilities exist which speed execution of batch files and make them run from RAM memory rather than disk. Most computer clubs and BBS system carry these batch file compilers. One popular batch compiler is named BAT2EXEC and was produced by PC Magazine several years ago. Batch files will FLY once they have been compiled and run from memory rather than disk. Another batch file speedup trick uses a "ramdisk" as follows. Remember the DOS VDISK command in our second DOS tutorial? Many DOS experts put commonly used batch files in a virtual or RAM disk in memory where a batch file runs quickly. This is one trick which can turbocharge batch file operations. ---------------------------------------------------------------- AUTOEXEC.BAT FILE BASICS - THE WAKEUP CALL TO YOUR COMPUTER ---------------------------------------------------------------- The AUTOEXEC.BAT file starts your computer exactly the way you want. It allows you to customize the machine to your liking as the computer comes to life. You can cause the AUTOEXEC.BAT file to print a startup menu of choices, load one particular program, execute another batch file or other useful tasks. The AUTOEXEC.BAT file is the first file DOS runs after loading itself and configuring the computer. The AUTOEXEC.BAT file must be on the same disk as DOS when the computer starts. The AUTOEXEC.BAT file is a special batch file which MUST be placed in the main or root directory of a disk to function properly. An AUTOEXEC.BAT file can always be modified, enlarged, edited, or deleted later as you wish. Sometimes it is useful to have several AUTOEXEC.BAT files. Each on a different startup disk to operate different programs! An AUTOEXEC.BAT file, like all batch files, can be modified with any word processor, DOS EDIT or EDLIN text editor. Before tinkering with your AUTOEXEC.BAT file, make sure you do not accidentally over-write or destroy your current AUTOEXEC.BAT file. If necessary, rename your current AUTOEXEC.BAT file (using the rename or REN command) and make a new file while saving the old one "just in case." Never edit files on your original DOS disk, work on a copy! This wise advice applies to ANY computer file. Save a backup copy; never work on the original. Examine the next batch file: copy con AUTOEXEC.BAT (press enter) 123 (press enter) ^Z (press enter) This means (first line) create a file named AUTOEXEC.BAT as typed from the keyboard or con (console). Then (second line) start program named 123. The (final line) end of batch file preparation - stash it on the disk. Since the first and last lines prepare the batch file, this program really has only one line whose purpose is to start a specific program (123.EXE) each time the computer is turned on. When finished you'll see a file named AUTOEXEC.BAT on your directory listing screen which contains automatic startup instructions. If this file were placed on your main DOS disk it would try to start a program such as 123.EXE if such a program existed there. And since it is AUTOEXEC.BAT this would be the first file run each morning when you turn on your computer. You can also start the AUTOEXEC.BAT by typing autoexec and then pressing enter. To take a "peek" at the contents of an AUTOEXEC.BAT file (or any bat file) simply use the type command. Remember to use Ctrl-S key combination to pause the screen if the display flashes by too quickly. Example: C>type AUTOEXEC.BAT (display file contents) Example: A>type b:AUTOEXEC.BAT (display file on the B: drive) Example: C>type AUTOEXEC.BAT>PRN (display file contents on printer) Here is another AUTOEXEC.BAT file, this time from a hard drive computer. It provides a higher degree of control and direction that a computer user might need for hard drive customization. path \dos;\reflex;\wp;\util;\doc;\nor;\bat prompt $P$G cpu n verify on blank mode bw80,r dispclk type menu.txt Let's examine this more complicated AUTOEXEC.BAT file in greater detail: The first line after establishes a path command to help DOS search every subdirectory on the hard disk -you don't have to switch around to different areas of the disk, DOS will search for you since it knows the various subdirectory "paths" to take. The second line alters the cursor prompt to always display your current location and subdirectory. Instead of seeing C> you view a more informative C:\DOCS> for example. The third line is a reference to the speed the computer will operate at and is a unique command to a particular brand of machine (cpu n means start the central processing unit chip at normal speed.) Cpu is really CPU.COM, an external file which sets the computer's processing speed. Your DOS disk may or may not contain the file CPU.COM. This highlights the ability of the AUTOEXEC.BAT file to start or load other programs and is very useful! The fourth line turns on the verify function for file copying. The next line instructs the DOS mode function to switch to black and white display, 80 columns wide and shift one column to the right for alignment. We are setting the hardware the way we wish. We could also configure the modem or printer with the mode command. Next we ask DOS to tell us the time and date. Run the program DISPCLK.COM, an external program stored on disk. The final line instructs DOS to type to the screen a text file containing a simple menu for the monitor to display. Menu.txt probably gives us choices of programs and thus calls other batch files. ---------------------------------------------------------------- BATCH FILE COMMANDS AND USE ---------------------------------------------------------------- In addition to the normal DOS commands, batch files have eight special subcommands. At the end of this section we will provide some interesting batch files which you can use or edit on your computer. The special batch commands are: --- REM --- The rem command sends a message to the screen or simply documents or notes a part of a batch file's operation. You should use REM extensively to document long detailed batch files so you can revise things and locate portions of the program if you decide to change the batch file later. Remarks can be up to 123 characters long. REM does not cause any operation, it merely documents what you want to say or do. Example: C>REM this is the location of menu operations In DOS 2.0 the REM command could be replaced with a period or dot, but this is not true in DOS 3.0 and above. Example: C>. this is the location of menu operations --- PAUSE --- Stops batch file execution on a temporary basis until you press a key. Thus you can pause a batch file and do some operation (perhaps changing a floppy disk) and then continue when you strike a key. Very useful. Example: B>PAUSE Example: B>PAUSE This is an optional message, pardner! In the first example, no message is displayed. --- ECHO --- Turns display listing of commands on/off. It can also send a message to the screen. It is frequently turned off to remove excessive screen messages. Normally, with ECHO on, screen messages are sent to the screen which can be distracting. To suppress them use the first example. To restart the messages use the second example. To add a message with the ECHO command see example three. REM or remark command can also send a message to the screen but NOT with ECHO turned off! Example: A>ECHO OFF Example: A>ECHO ON Example: A>ECHO It's raining cats, dogs and computers Example: A>@ECHO (don't display this particular line) --- PARAMETERS AND MARKERS ---- This is NOT a batch file command like ECHO or PAUSE. Instead parameters are additional pieces of information or "modifiers" which follow DOS commands. Example: C>format b:/s In the above, format is the command while b: and /s are the parameters. Parameters modify the basic operation of a DOS command but are not required by the command to operate. A batch file can also accept parameters such as a word, filename, symbol, drive letter or any useful character or group of characters! Markers placed inside the batch file listing signify which parameter goes where. Markers are made from a percent sign (%) and a single digit between 0 and 9 for a total of ten markers available (remember, zero is a number too.) Here are the ten markers: %0 %1 %2 %3 %4 %5 %6 %7 %8 %9 Let's use an example. Pretend that DOLITTLE.BAT is on your floppy. Within its listing of commands there might be this single line: ECHO %0 %1 %2 (ECHO shows messages on the monitor) If at the DOS prompt you typed: B>DOLITTLE fancy pants (then press enter) Your screen would show the following: ECHO DOLITTLE fancy pants. In this case, %0 has taken on the value at the start of the DOS command which is the first word "DOLITTLE". Meanwhile %1 has become "fancy" and %2 is now pants. Looking at this another way: DOLITTLE fancy pants | | | ECHO %0 %1 %2 Let's try a more useful example. Pretend you had a large file of word processing files containing bills you have to pay from time to time. You need to look up bills or amounts in the file accounts.txt which is in plain ASCII (english) text from your word processor. The DOS FIND utility can search large files for specific words, strings or characters. The general format for the FIND command is: FIND "text" filename. FIND is located in the file FIND.COM on your DOS disk and must be present with the batch file to be used. A simple batch file possibly named GET.BAT could do this: ECHO OFF ECHO searching for data . . . . FIND "%1" %2 ECHO Finished, boss Start the batch file get.bat with search data like this: C>get grocery accounts.txt (first word starts get.bat, second word is the item to search for, third item is the file to search.) As a result, you will get a report of the line where the word "grocery" is found within the file accounts.txt. This could also be used to search a telephone list or list of employee names and addresses. A powerful idea for a short batch file! --- GOTO --- Jumps to a labeled set of commands within the batch file. The general format for the command is GOTO LABEL where LABEL is a line in the batch file which must start with a colon (:) followed by a name up to eight characters long. A simple, but useless batch file illustrates the GOTO command by looping around in circles doing the same task endlessly. Example listing for batch file: ECHO OFF :kitty ECHO watch this fill your screen over and over, folks GOTO kitty Note! On some versions of DOS it is necessary to include one blank line at the end of this file. In the above example, just press Enter/Return key one extra time after the line "GOTO kitty" and then save the batch file. The above batch file will continue to print the remark line over and over since it always returns to the start. Tap Ctrl-Break to stop this silliness. The true usefulness of the GOTO command is best understood by allowing the GOTO within a batch file to transfer control elsewhere within its listing rather than to the line immediately next in sequence. You can thus cause varying useful results depending on a conditions present. Choices and different outcomes are a trademark of savvy batch file use. --- IF --- Allows conditional operation of a command. This is a fancy way of saying you can cause a batch file to make decisions based on a logical condition or input then do something. The usual syntax of the IF command is IF CONDITION COMMAND. Let's take this apart and examine the concept. In the situation IF CONDITION COMMAND: COMMAND is any normal DOS or batch file command and CONDITION is one of three possible tests that yield true or false. Example: IF %1==w GOTO dog (we'll explain this in a bit) Example: IF %3 == 80 MODE BW80 (we'll explain this in a bit) The three possible tests are: 1. The ERRORLEVEL condition (i.e., a specific number is found). 2. The STRING COMPARISON. (i.e., two strings are equivalent or not.) 3. The FILE EXISTENCE condition. (i.e., if a file exists or not.) In true full-featured programming languages many other logical tests might be allowed, but for batch files these are the only three tests. Let's examine the three more closely. Then illustrate with an example. 1. ERRORLEVEL is a number which tells DOS whether the last program run was successful. If so the errorlevel is zero (0) anything else above zero means unsuccessful. 2. STRING COMPARISON, the second conditional test, is always indicated in a batch file by double equals signs (==). A test is designated by the condition IF string1 == string2. This is frequently used with parameters or markers such as: IF %3 == 80 MODE BW80. 3. In the final and third conditional test, FILE EXISTENCE, the usual format is IF EXIST d:filename.ext. which checks for a certain file on a certain drive. You can thus check for a certain disk or file before continuing the batch file process. Pathnames are not allowed (d:\slip\and\slide). Let's try a batch file example to illustrate the use of STRING COMPARISONS to make a choice in how the batch file does its work. In a way, this is a menu program. Pretend you have two software applications. One is a word processor named WORD.EXE whose command to start is WORD and the other is a spreadsheet named LOTUS.EXE whose command is LOTUS to start. If we prepared a simple batch file called go.bat whose listing is below, we could start one or the other program by using either the command: A>go w (to start the word processor) OR THIS: A>go s (to start the spreadsheet). Notice how the "w" or "s" is picked up by the batch file and sends the program either one direction or the other in the example below. The remarks lines which begin with REM in the batch file give you a clue about the operation of the program but are not themselves commands. The end result of this batch file is a saving of keystrokes for frequently used software (the word processor and spreadsheet) and could be expanded to start many other software packages. REM This batch file selects one of two choices based on input REM The next line turns off screen echo to avoid screen clutter ECHO OFF REM Begin test for one of two choices REM Next two lines use percent signs as markers for "w" or "s" keys IF %1==w GOTO dog IF %1==s GOTO cat REM Next line forces goto end if no match is made for w or s GOTO end :dog REM Next command starts word processor, WORD.EXE WORD GOTO end :cat REM Next command starts spreadsheet, LOTUS.EXE LOTUS GOTO end :end REM Next line switches to root directory and ends the batch file CD\ ECHO Batch file done, bye bye! --- SHIFT --- Re-assigns the relationship of parameters to markers. It changes their values. And it does it in a very odd way . . . Remember that there are only ten markers available to a batch file to hold the parameter values as we mentioned above. Here they are: %0 %1 %2 %3 %4 %5 %6 %7 %8 %9 However you can raise the limit of 10 parameters in a batch file using the single word SHIFT. When this command is encountered in a batch file, all the parameter and marker pairings are shifted one unit to the left. Whatever was assigned to %0 is lost. A diagram to visualize. Before a SHIFT command is issued the parameters and markers might be: %0 %1 %2 | | | dog cat computer After the SHIFT command we would see: %0 %1 %2 | | | cat computer Notice that dog is lost, %1 becomes computer and %2 is left vacant unless it takes a new parameter from %3 (if %3 had a parameter). The effects of the SHIFT command are wide ranging throughout the batch file and provide great flexibility and a range of parameters greater than ten values. --- FOR..IN..DO --- Allows iteration (repetition) of actions or commands. The command is similar to a FOR...NEXT...STEP loop programmers use. This command lets you repeat an action several times. The command is rather subtle and could be thought of as a three part command. The syntax is: FOR %%Variable IN (Set) DO Command Let's look more closely at the three parts: FOR %%Variable IN (Set) DO Command ============== ======= ========== | | | part 1 part 2 part 3 Translating into English this means: FOR a certain batch file variable withIN a SET of filenames or commands DO a certain action. The %%VARIABLE is a one-letter variable which must have a double %% prior to the letter to distinguish it from single % markers we have seen earlier. The SET portion of the command is always in parenthesis as (SET). The SET represents filenames or DOS commands you want the %% variable to assume while the command is executing. A space is used between entries. Pathnames are never allowed but wildcards such as *.* are acceptable. If the SET contains DOS command then only the %%VARIABLE is used. The COMMAND is a DOS command or batch subcommand. One or several of these commands will contain the %%Variable in it. Let's try an example. Pretend by you want a batch file to present the DOS version then clear the screen and finally issue the directory. We could do this in three lines by: VER CLS DIR/P However, with the command FOR..IN..DO we can do this in one line: FOR %%T IN (Ver cls Dir/P) DO %%T Notice how each DOS command is separated by a space. ? and * are NOT allowed within any command within the SET. Use a colon : instead of a space within the set when passing parameters to programs. You can issue the FOR..IN..DO batch file subcommand at the DOS prompt by dropping one of the percentage signs % on the variable. Let's move on to some practical and fairly interesting examples . . . ---------------------------------------------------------------- BATCH FILE PROJECTS FOR YOU TO TRY! ---------------------------------------------------------------- The following batch files do real work and can teach you some fascinating principles. To save typing each example, here's a shortcut: simply load this file, BATCH.TUT, from the PC-Learn disk or hard drive into your word processor. Next, delete the tutorial and batch files you don't need, keeping only the batch file lines you require. Move all lines of the batch file to the far left margin then save the batch file back to disk in plain ASCII text with a permanent batch file name such as CANDY.BAT, GO.BAT or PRINTER.BAT which you can easily remember. Feel free to change or add things to these batch files with your word processor since that's the point - batch files are flexible! Note the liberal use of the remarks or REM lines in some batch files to explain how things work. If you like, delete all REM lines to save typing time, space and speed program execution! ---- Fast freespace batch file ---- This is a short but useful batch file. It reports the amount of freespace on a disk by using the FIND command in DOS to search out the line containing the word "free" in the DOS DIR command. Program name: TELLFREE.BAT ECHO OFF CLS ECHO CHECKING FOR FREE SPACE ON DISK DIR | FIND "free" You could modify the last line to DIR A: | FIND "free" to locate the free space on the A: drive. The piping symbol | , discussed in a previous DOS tutorial illustrates how one command (DIR) can "pipe" its output into the FIND command. You MUST have the DOS file FIND.EXE on the same disk so that the DIR command can use it. The word "free" is case sensitive and must MOT be typed in capital letters since the FIND command is case sensitive. Obviously, to use this small program, at the DOS prompt just type TELLFREE then press the return or enter key. You could also name this batch file T.BAT if you wanted to only type a single letter and save additional keystrokes. ---- Fast deletion batch file ---- This is a short batch file with some powerful wrinkles for speedy file deletions. It could be modified in many ways. Program name: DB.BAT ECHO OFF CLS ECHO Ready to delete ALL files on B: drive ECHO Press control-break keys to abort or ECHO any other key to continue PAUSE REM Following line does the deleting ECHO Y | DEL B:*.* ECHO DONE! This is an odd batch file using some powerful DOS secrets. Line four reminds us we are about to delete all files on the B: drive and gives us the chance to abort using the control-break key combination which works to abort all batch files. The pause command on line six halts operations and waits for our keypress. Line eight shows the real power of DOS in a one line command which uses ECHO to pass the keystroke Y (meaning yes) via the pipe operation of DOS represented by the vertical bar |. This effectively means that the deletion of all files on B: drive represented by *.* will take place WITHOUT pausing for the traditional Yes/No request. The name of the batch file, DB.BAT reminds us that its use is to delete all files on B: drive or DB, for short! ---- Fast formatting batch file ---- This batch file will speed your disk formatting. Its name F.BAT means format disks, and it gives you some choices and illustrates other batch file tricks. There are three ways to use it: for formatting A: drive, B: drive, or both A: and B: drives. Note the minimum number of keystrokes required and how the batch file determines your choice by using parameters. This batch file also requires a small text file called yes.txt which shows how a file can be used to redirect input to a DOS command in place of the keyboard. It is explained below. Be sure to prepare YES.TXT or F.BAT will not work! To start this batch file you MUST chose one of the following. The space between letter characters is important. To format only A: drive, at DOS prompt enter F A To format only B: drive, at DOS prompt enter F B To format both A and B drives, at DOS prompt enter F AB In the above commands, the A, B or AB will be inserted into the batch file in the location of the symbol %1 as noted earlier in this tutorial. Program name: F.BAT ECHO OFF CLS ECHO FORMATTING DISKS NOW! REM This batch file selects one of three choices based on input REM Begin test for one of three choices IF %1==A GOTO DOG IF %1==B GOTO CAT IF %1==AB GOTO MOUSE REM Next line forces goto end if no match is made GOTO end :DOG FORMAT A:<yes.txt GOTO end :CAT FORMAT B:<yes.txt GOTO end :MOUSE FORMAT A:<yes.txt FORMAT B:<yes.txt GOTO end :end Lines 18 and 19 provide formatting of B: immediately after formatting of A: is finished. A short but very powerful batch file. Note, how the batch file cleverly uses redirection with the < symbol discussed in our earlier DOS tutorial to send the "stored keystrokes" in the file yes.txt to the format command so you do NOT need to type Yes/No each time the computer formats a disk which is usual when using the format command. Redirection is a very powerful DOS operation. You will also need the file YES.TXT as discussed below. Program name: YES.TXT This is a very simple file. Start your word processor, DOS Edlin or even use the COPY CONsole command earlier. This tiny file contain a "y" character and two carriage returns and serves as an input file to take the place of the keyboard as explained above. It provides the format command with "simulated" keyboard response of Y (Yes) so the batch file above can continue. Using Copy Console command (which is one method to prepare YES.TXT): COPY CON YES.TXT (press enter) y (press enter) (press enter, skip to new line) (press enter, skip to new line) ^Z (press F6 to end and write file to disk) ---- Make a menu batch file project ---- The next project is actually four simple batch files which work together to provide a "poor man's" menu program for a hard drive. Note the automatic switching between subdirectories provided by the files 1.bat, 2.bat and 3.bat. Obviously you could expand this to include menu choices for more options. Type in each batch file program and save on your hard drive. Place all files in the root directory of your hard drive, usually C:\ When ready to start, simply type M, then press enter key. Notice how M.BAT runs one of the other three files, 1.BAT, 2.BAT or 3.BAT. Notice also how when those batch files are done, they automatically run M.BAT to return from where they began and again display the menu screen. Program name: M.BAT REM Third line turns off echo so commands are not repeated to REM the screen twice, avoids screen clutter ECHO OFF REM Next line clears the screen CLS REM Next line suggests option 1 which will run 1.bat ECHO PRESS 1 FOR WORD PROCESSOR REM Next line suggests option 2 which will run 2.bat ECHO PRESS 2 FOR SPREADSHEET REM Next line suggests option 3 which will run 3.bat ECHO PRESS 3 FOR DATABASE ECHO PRESS ENTER KEY AFTER SELECTION IS MADE Program name: 1.BAT ECHO OFF REM Fourth line switches to a subdirectory containing your REM word processor using the cd or change directory command CD\WP REM Seventh line starts your word processor, named word.exe REM Substitute the startup command for your word processor WORD REM Eleventh line changes out of word processing subdirectory REM and goes back to the root directory when word processor REM is finished CD\ REM Final line restarts the menu program m.bat M Program name: 2.BAT ECHO OFF REM Fourth line switches to a subdirectory containing your REM spreadsheet using the cd or change directory command CD\SPREAD REM Seventh line starts your spreadsheet, named lotus.exe REM Substitute the start command for your spreadsheet LOTUS REM Eleventh line changes out of spreadsheet subdirectory REM and goes back to the root directory when spreadsheet REM is finished CD\ REM Final line restarts the menu program m.bat M Program name: 3.BAT ECHO OFF REM Fourth line switches to a subdirectory containing your REM database using the cd or change directory command CD\DATABASE REM Seventh line starts your database, named db.exe REM Substitute the start command for your database DB REM Eleventh line changes out of database subdirectory REM and goes back to the root directory when database REM IS FINISHED CD\ REM Final line restarts the menu program m.bat M ---- Printer Control Batch file ---- Some of the best kept DOS secrets are fascinating. If you have a standard dot matrix printer connected to your computer, you can use simple batch files to change the typeface and other features your printer provides. The reference booklet which accompanied your printer discusses printer control codes. For example, on Epson compatible printers you will note in your printer book that "emphasized printing" has the DECIMAL control code 27 69. Let's write a batch file to take charge of our printer! Program name: E.BAT ECHO OFF CLS ECHO SETTING PRINTER TO EMPHASIZED MODE ECHO (ALT 155)(ALT 69) >PRN ECHO DONE The fourth line contains a secret trick. The code we need to send is 27 69 according to our printer book. When preparing this batch file with EDLIN, COPY CONsole or your word processor, you must send the printer control code 27 then 69 to the printer. In line four after typing the word "ECHO" then a blank space, hold down the ALT key then press 155 on the FAR RIGHT NUMERIC KEYBOARD. When done entering the number, release the ALT key. On most computers, the cents symbol will appear which the printer will accept as the "escape code 27." DO NOT type the left and right parenthesis marks which appear on line four: ( ), they are only for clarity. Next press ALT 69 which produces the E symbol. You could also just type capital E. Next type >PRN which sends this code to your printer. Note that there is NO blank space between (ALT 155) and (ALT 69). The code 155 is substituted for 27 but the 69 is unchanged. Why 155 rather than 27 for the escape code? An explanation: Printer control codes begin with code 128, thus escape character 27 is generated by using 27+128 = 155. An necessary trick for this batch file. We could send SEVERAL codes by adding more lines to the batch file to set letter quality, pica font, line spacing and tabs, then type the letter to the printer (ECHO LETTER.TXT>PRN) and finally reset the printer. Your printer book discusses these decimal control codes. If we wanted to send a formfeed to the printer (eject paper,) the printer reference book suggests control code 12, therefore 12+128 = 140. So the fourth line in the batch file would read ECHO (ALT 140) >PRN. The bell sound (decimnal code 7) is generated by 7+128 = 135. The batch file would change to read ECHO (ALT 135) >PRN. Some printer features are controlled by SINGLE control codes while other features are controlled by MULTIPLE escape sequence codes which always begin with 27 followed by additional numbers. Escape code 27 is always translated to ALT 155 when DOS and batch files transmit the printer control information. Within software programs the codes may use a different format: \027E for example. Many other printing features can be turned on using short batch files. For example, double strike printing uses the decimal code 27 71. In the batch file you could use ECHO (ALT 155)(ALT 71) >PRN. You can also turn on a COMBINATION of several features in one longer batch file to control several features. Just add more lines and codes to the batch file! To reset the printer when a printing job is finished: code 27 64. Search out these printer codes in your printer manual and let a batch file do the hard work! One of the best batch file tutorials to date was published in two parts in the November and December 1991 editions of PC Computing Magazine. Contact your library for back issues or contact PC Computing at Back Issues Dept, PC Computing Magazine, Ziff Davis, POB 53131, Boulder, CO 80322. Back issues currently cost $6.00 each. The bibliography/suggested reading list with PC-Learn provides additional reading suggestions to advance your batch file knowledge. Tutorial finished. Have you registered PC-Learn to receive your bonus disks? Registration is encouraged. Shareware works on the honor system! 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