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BATCH FILES FOR EFFICIENCY

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              BATCH FILES FOR EFFICIENCY - GETTING REAL WORK DONE 

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       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 DOS. 3) Use the newer DOS EDIT text 
       editor available in DOS version 5.0 4) 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)
       
       WARNING! Be careful when preparing batch files since you will 
       automatically overwrite and destroy any PREXISTING batch files 
       of the same name! 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!
       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. 

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          AUTOEXEC.BAT FILE BASICS - THE WAKEUP CALL TO YOUR COMPUTER 
       
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       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 this 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 this disk provides 
       additional reading suggestions to advance your batch file 
       knowledge. 
                                                                  
       Tutorial finished. Be sure to order your FOUR BONUS DISKS which 
       expand this software package with vital tools, updates and 
       additional tutorial material for laptop users! Send $20.00 to 
       Seattle Scientific Photography, Department LAP, PO Box 1506, 
       Mercer Island, WA 98040. Bonus disks shipped promptly! Some 
       portions of this software package use sections from the larger 
       PC-Learn tutorial system which you will also receive with your 
       order. Modifications, custom program versions, site and LAN 
       licenses of this package for business or corporate use are 
       possible, contact the author. This software is shareware - an 
       honor system which means TRY BEFORE YOU BUY. Press escape key to 
       return to menu.