Use the following syntax for the GRAPHICS command:

GRAPHICS printer [drive]:pathfilename /R /B /LCD /PRINTBOX:STD

printer is the type of printer you are using. Table 13.3 lists the values you can use for the printer parameter. If your printer is not listed, it might be compatible with one of the other printers on the list. Refer to your printer's instruction manual for details. If you do not specify a printer, DOS assumes the GRAPHICS printer type.

[drive]:pathfilename is the drive, path, and filename of a printer profile file that can be used by the GRAPHICS command for your printer. This file supports the printers of other manufacturers. If your printer doesn't fit into one of the categories supported by GRAPHICS, you can create a custom printer profile for use with GRAPHICS. The filename parameter refers to the profile file, which specifies how graphics are translated for various printers. The profile file is an ASCII text file with two types of information for each printer in the file. A profile can include information about how the printer is controlled, such as selecting printer colors or adjusting the darkness of the printed piece. The second section of the profile lists the translation from the screen to the printer.

/R forces the printer to print a monochrome text screen as you see it—black background and white text. When you use the /R switch with a color screen, the darkest colors (black or blue) print as black, light colors appear as white or light gray, and other colors print as different shades of gray on a grayscale for contrast. If you don't use the /R switch, all onscreen information that is white prints as black, and all black onscreen information (usually the background) prints as white. The paper color in the printer is assumed to be white.

/B prints the background color. Use this switch only if you have a color printer and after you specify COLOR4 or COLOR8 as your printer type. If you try to use the /B switch with a black-and-white printer, DOS displays the following message:

The /B switch is invalid with black and white printers.

/LCD is a switch designed for use with the IBM PC-Convertible, which comes with a small liquid-crystal display (LCD) screen. /LCD forces the printer to print the screen as it appears, with the size of the screen and characters smaller than on normal monitors. You also can use this switch with any other laptop computer that has an old-style, smaller LCD screen like the IBM PC-Convertible. Most laptops now have a full-sized LCD screen and don't require the use of this switch.

/PRINTBOX:STD sets the printbox size to standard or normal size, as it appears on monochrome and VGA monitors of standard size and shape. You use this setting to print the screen when you work with Quattro Pro, Microsoft Word, or other programs in graphics mode. You also use this setting to print the contents of a narrow LCD screen if you want it to appear as if it were on a standard monitor. By typing /PRINTBOX:LCD, you can use this switch to force the printer to print in LCD mode (a longer form of the /LCD switch, shown earlier). You can abbreviate the /PRINTBOX switch to /PB.

Suppose that you have an IBM ProPrinter printer. If you use a monochrome system and want to print a screen image with the background as black and the text as white, enter the following command at the DOS prompt:

GRAPHICS /R

After GRAPHICS loads into memory, you can create the screen of interest and press Print Screen to print to the printer.

To print eight-color images (including the background color) on an IBM PC Color Printer with a CMY ribbon installed, type the following command:

GRAPHICS COLOR8 /B

On the PC-Convertible with an attached full-sized monitor, you can send the screen image to the IBM PC-Convertible thermal printer by typing the following:

GRAPHICS THERMAL /PB:STD

Changing the command to either of the following prints the image as it normally appears on the liquid-crystal display:

GRAPHICS THERMAL /PB:LCD
GRAPHICS THERMAL /LCD

You should remember the following guidelines when using the GRAPHICS command:

The external PRINT command uses the following syntax:

PRINT <switches> filename1 /P /T /C filename2 /P /T /C...

You can replace <switches> with any of the switches listed in Table 13.4. filename1 is the drive, path, and filename of the first file you want to print, and filename2 is the drive, path, and filename of the next file you want to print. The ellipsis (…) means that you can list more files. You also can use wildcards in the filenames.

Like GRAPHICS, PRINT leaves a portion of itself in memory after you issue the command, and the switches change how the PRINT command works. You can specify the optional switches in Table 13.4 only when you first issue the PRINT command. The other switches (issued after the filenames) can be issued at any time, however:

If you enter filenames without a /P, /C, or /T switch, DOS uses the /P switch as a default so that all files are placed in the queue for printing. If, at the prompt, you type PRINT with no switches, a list of all files in the queue appears. This list includes the name of the file that is currently printing and the order of files yet to print. This command also displays any error messages. If, for example, you forget to turn on the printer, the following error message appears:

Errors on list device indicate that it may be off-line. Please check it.

You do not have to enter the names of all the files to print at one time. You can issue the PRINT command several times to add or remove files from the print queue. You can specify the parameters that affect the way PRINT operates (those in Table 13.4), however, only when you first issue the command. After you first issue the PRINT command, you use the command only to enter filenames for printing or to cancel printing.

If you enter the PRINT command for the first time without specifying a device, PRINT prompts you for a device name. The default, PRN, is the first parallel port (LPT1) on your computer. Pressing Enter at the DOS prompt accepts the default.

If you are in no hurry to collect the printed output of files and want to use the computer while the printer prints your files, you can readjust the default installation settings for PRINT. By changing the /M:ticks2 or /S:ticks3 settings, you can give your computer better response time. To alter the default settings, you can type the following when you invoke the PRINT command for the first time:

PRINT /D:PRN /M:1 /S:25

If you are unconcerned about the sluggishness of the keyboard, you can improve the speed of the background printing by altering the buffer size, as well as by adjusting /M:ticks2 and /S:ticks3. You might type the following command, for example:

PRINT /D:PRN /B:16384 /M:1 /S:25

Experiment with these variables until you find a setting that is acceptable. A sluggish keyboard is not always tolerable. If the response time is too slow, you can make errors; for example, you might assume that a program didn't accept your keystrokes and try to retype the command, whereas the program was only waiting to regain control.

By using a combination of the /P, /T, and /C switches, you can adjust the order in which the files print. Suppose, for example, that you want to print four files: LETTER1.TXT, MEMO1.TXT, REPORT1.TXT, and REPORT2.TXT. Type the following on the command line:

PRINT /D:PRN LETTER1.TXT /P MEMO1.TXT REPORT1.TXT REPORT2.TXT

If you then decide that you want to print REPORT2.TXT before REPORT1.TXT, type the following command, which removes REPORT1.TXT from the print queue and adds the file to the end of the queue:

PRINT REPORT1.TXT /C REPORT1.TXT /P

You can cancel all files to be printed by typing the following command:

PRINT /T

As you are using PRINT, you should keep the following guidelines in mind:

A parallel port transmits data by transferring an entire byte at one time. Because of the way data is transferred, parallel ports are typically used to send information to a printer. To help control your printer, you can use the MODE command to adjust the number of lines per inch and columns per line on your printer and to set the retry feature.

MODE LPTn: cpl,lpi, P

MODE LPTn: COLS=wid, LINES=lpi, RETRY=action

MODE LPT1:,,P

MODE LPT1 RETRY=B

MODE LPT1 RETRY=P

MODE LPT2:132,8

You can use another option of the MODE command to alter the functions of the serial ports. This command works in a way similar to the parallel port adjustments. DOS changes the parameters that are sent to and from the device driver.

The acceptable serial ports are COM1, COM2, COM3, and COM4. The serial port can receive and transmit data only one bit at a time. The signaling rate (the number of times per second that data is transmitted) is the baud rate. The amount of data transferred in a second is referred to as the bps (bits per second).

You can use the MODE command to adjust the baud settings and change the amount of data sent in a fixed time. Although it is called a baud setting, the numbers used are actually the number of bits transmitted per second. Acceptable baud settings are 110, 150, 300, 600, 1200, 2400, 4800, 9600, and 19200. You need to use only the first two digits of the number to set the baud rate.

The most common devices attached to a serial port that you need to set from DOS are serial printers and plotters. Although modems are serial devices, you usually don't adjust them from DOS. Communications programs, however, use the DOS functions to make adjustments to the serial ports.

Use the following syntax to change the serial port:

MODE COMy: baud,parity,databits,stopbits,P

The elements of the commands are as follows:

You also can use the following syntax:

MODE COMy: BAUD=baud PARITY=parity DATA=databits STOP=stopbits RETRY=action

All the variables in this version of the MODE command are the same as in the previous version. The only new one is action, which is the message you want DOS to return when the port is busy.

With versions of DOS before Version 4.0, the retry feature provided two choices when a timeout error occurred: no retry or continuous retries when you included the P option. When data is sent to the printer, the port expects to see signals from the printer indicating that it received the data. If the port doesn't receive any signals within a particular period of time, a timeout error occurs. By default, DOS does not try again to send information to the printer and returns an error message to the screen. If you include the P option, DOS continuously tries to send the data; this action prevents the error message from being displayed. The Ctrl+Break key combination stops the retry process.

With DOS 4.0 and later, more retry options are available. If you do not specify a retry option, DOS doesn't try again to send data when a timeout error occurs. When you use the retry option, you can select from the following four options:

MODE COM1 2400,N,8,1

MODE COM1 24,N,8,1

MODE COM1 BAUD=24 DATA=8 STOP=1 PARITY=NONE

The final MODE setting you can use with ports is the command to redirect a parallel port to a serial port. Typically, you use this setting if you want to redirect printer output to the serial port for use with a plotter or serial printer.

MODE LPTn:=COMy:

MODE COM2 2400,E,7,2

MODE COM2 BAUD=24 DATA=7 STOP=2 PARITY=EVEN

MODE LPT1=COM2

When you press a key on the PC keyboard, a character appears onscreen. If you continue to hold down the key, the pressed character repeats onscreen. The number of times per second the key repeats is known as the typematic rate.

The syntax for the MODE command that changes the typematic rate is as follows:

MODE CON RATE=rate DELAY=delay

rate is the number of repetitions per second. The rate parameter can have values in the range 1 through 32. These values represent a repeat rate of from 2 to 30 characters per second (the higher the value, the faster the repeat rate). The default value is 20 for an IBM AT and 21 for an IBM PS/2, which is equivalent to approximately 10 characters per second.

The delay parameter is the time delay before DOS starts repeating a key. The delay is specified in .25-second intervals. The range for the delay is 1 through 4, making a total possible delay of 1 second.

To set the keyboard so that the delay before the key repeats is 0.75 second and the rate value is 24, type the following:

MODE CON RATE=24 DELAY=3

The redirection symbols are the greater-than and less-than signs. If you think about it, these symbols look like arrows (> or <) that show the input's source and destination. Use the following syntax for redirecting a program or command's input:

command < inputdevice

The syntax for redirecting a program or command's output is shown in the following:

command > outputdevice

The syntax for redirecting and appending to an existing file is shown in the following:

function command >> outputdevice

In each syntax shown here, inputdevice is the source of the input, outputdevice is the destination of the output, and command can specify almost all applications programs or DOS commands. With the redirection command, you can use any DOS output device as an outputdevice, and you can use any DOS input device as an inputdevice.

Normally, redirected input comes from a file. Some devices, however, such as a mouse or bar-code reader, can also be used as a source of input. You can write a file that consists of the keystrokes used to operate a program, for example, or you can use the output from a mouse as the input for a program.

Most DOS users redirect output more often than they redirect input. The two most common places to redirect output are to the printer or to a disk file. The following command, which redirects the output of a directory to the printer, is a common example of redirection:

DIR > PRN

When you issue this command, DOS redirects the output (the directory listing itself) to the PRN device instead of sending the listing to the screen. This command produces a hard-copy listing of the directory.

Another common use is redirecting output to a file. To review the statistics of the MEM /C command, for example, type the following command:

MEM /C > CLASSIFY.MEM

When you use redirection commands with pipes and filters, discussed later in this chapter, the command becomes even more powerful.

If you want to redirect to the printer a copy of your disk's directory structure and a list of the files on your hard disk, type the following:

TREE C: /F >PRN

The TREE command does not supply a directory listing that includes file sizes. If you want to create a full listing of all the directories on your hard disk by using redirection to append the output of the command, you specify that each directory be listed and then specify that the output be appended to a file. You then can print the full list. To perform this task, you type a command similar to the following for each directory:

DIR C: /S >> FULLIST.DIR

The DIR command lists the files in all the directories on drive C. The /S switch causes the DIR command to display all subdirectories. You can then substitute the names of other drives for C.

If you are testing programs that require a large amount of user input, the following redirection method is useful. For example, you can type the following:

PROGRAM < C:TESTPAT

This command results in the file TESTPAT supplying the input to PROGRAM. The redirection process enables you to construct a file that contains the correct keystrokes needed to oper-ate a program. You then can test the program's basic operation before you include the error-trapping sequences. These sequences handle the situations when the user presses an incorrect key.

The following are some helpful rules to know when using redirection:

The syntax for the MORE filter, which has no switches, is shown in the following:

MORE

MORE is commonly used in the following way, where filename is the input file:

MORE < filename

Or, it is used in the following way, where command is any command or program:

command | MORE

MORE collects—and saves in a temporary disk file—information that normally goes to the screen. When a screen of input is obtained, MORE sends that information to the standard output device all at the same time. The text is channeled through the MORE filter until the end-of-file. Press any key when DOS displays the -- More -- prompt; this action displays the next screen. After all the information is displayed onscreen, DOS erases the temporary file created by MORE.

When you use MORE to pause directory listings, the filter serves a function similar to the /P switch that is available with the DIR command.

The most common use of MORE, however, is to pause the TYPE command. To read the contents of a README.DOC file one page at a time, for example, type one of the following:

TYPE README.DOC | MORE

MORE <README.DOC

Both syntax forms work identically. To see the contents of a file, you can use the TYPE command. If the output of the file flows off the screen, reissue the command by pressing F3, and add the pipe character (|) and MORE.

The following are some helpful rules to know when using MORE:

Use the following syntax for the FIND filter:

FIND /C /N /V /I "string" filename...

"string" specifies the ASCII characters for which you want to search, and filename is the full filename of the file to search. The ellipsis (…) indicates that you can specify more than one file to search.

/C causes FIND to count all the lines that contain "string". You use the /C switch to count the number of lines with the ASCII string; the text itself isn't passed to the screen.

/N causes FIND to include line numbers of the lines that contain the "string". You use the /N switch to locate the line numbers within the text file. The line numbers listed are the line numbers in the original text file, not just sequential numbers. If the third, fifth, and sixth lines in the text file contain the string, for example, the line numbers displayed are 3, 5, and 6—not 1, 2, and 3.

/V causes FIND to search only for lines that do not contain the "string". Only these lines are passed on to the screen.

/I makes FIND insensitive to case: Upper- and lowercase letters are considered the same.

If you use FIND without options, the filter reads each of the files you specify and displays all lines that contain the ASCII string you are looking for. DOS filters the information that normally goes to the output device. All lines that include the ASCII string are displayed onscreen.

Like the other filter commands, FIND is often used with redirection and piping. If you search a text file for lines that include specific information, redirecting the output to a file might be helpful. You then can use the list as a reference while you look at the whole of the original file.

You can use the FIND command to find all files that have a certain extension. To find all files with the extension .LET, for example, type the following command:

DIR /S /B | FIND ".LET"

Because the /S switch is used with this DIR command, all files whose names contain LET—either in the root or extension—are listed under the name of the directory containing them. Because the /B switch is used, the filenames are listed in the form FILENAME.EXT, with a period instead of spaces separating the filename and its extension. Therefore, you can search for .LET instead of LET. In this form, each filename is preceded by its directory path.

The DIR command with the /S option lists all the files on a disk. The output for DIR that normally goes to the screen is filtered through the FIND command. The output from FIND then is displayed onscreen.

You also can use the FIND filter with text files as a word-search utility. Suppose, for example, that you forget the name of the memo you sent to your boss, but you know that the file is either MEMO1, MEMO2, or MEMO3. You also know that you always use your boss's title, Supervisor, in memos. You can find the memo you need by typing the following:

FIND "Supervisor" MEMO1 MEMO2 MEMO3

When you issue this command, each line that contains Supervisor is listed. The listing appears in the following form:

---------- MEMO1
---------- MEMO2
Supervisor of Communications
---------- MEMO3

The following aresome helpful rules to know when using FIND:

Use the following syntax for the SORT filter:

SORT /R /+n

/R reverses the sort order, and n is the offset column for the sorting process.

The SORT filter processes information that normally goes to your screen or to another output device. The text from the input is analyzed on a line-by-line basis and sorted according to the ASCII binary values of the characters. This order is alphabetical, but SORT doesn't discriminate between upper- and lowercase letters.

When you use SORT with redirection or piping, more sophisticated sorting occurs. The most common use of SORT is to sort a directory listing into a text file, which you then can print.

The offset—the /+n option—in the command shows the leftmost column to be sorted. With a directory listing, you can sort by date or file size rather than by root name. Table 13.5 lists the offset values for a directory listing.

The sorted output appears onscreen; the original directory listing itself remains unchanged.

DIR  /ON

You can use redirection and piping, as well as the FIND and SORT filters, in many ways. In DOS 4.0, 4.01, or 5.0, for example, you can create a sorted list of the subdirectories in the root directory by using the process outlined in the next paragraphs.

To create a sorted list of subdirectories in the root directory, follow these steps:

The result is an alphabetical list of all subdirectories in the root directory.

The following are some helpful rules to know when using SORT: