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            BATCH FILES FOR EFFICIENCY - GETTING REAL WORK DONE 
  1. —————————————————————
     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. 
  1. —————————————————————
        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. 
  1. —————————————————————
                        BATCH FILE COMMANDS AND USE 
  1. —————————————————————
     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: 
  1. – 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 
  1. – 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.
  1. – 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! 
  1. – 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.
  1. – 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. 
  1. – 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 . . . 
  1. —————————————————————
                    BATCH FILE PROJECTS FOR YOU TO TRY!
  1. —————————————————————
     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! 
  1. — 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. 
  1. — 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. 
     
     
/data/webs/external/dokuwiki/data/pages/archive/computers/batch.txt · Last modified: 2001/11/08 10:19 by 127.0.0.1

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