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1. QUICK START ASK allows you to ask for input from the user in a batch file. The simplified syntax is ASK [prompt] [expected Keys] Prompt is a "quoted" string that will be printed by ASK. Expected keys is a list of key that you expect from the user. The result is testable by the "if errorlevel" statement in a batch file. For example (in a batch file): echo off ask "Do you want to run away (y/n)? " yn if errorlevel 2 goto no rem *** errorlevel 1 falls thru here. Now run away. away :no When the user runs this batch file, he will get this prompt: Do you want to run away (y/n)? _ He can press the 'y' or the 'n' key. If he presses the 'y' key, errorlevel will be set to 1 (because y is the first character in the expected keys list) and away will be run. If he presses the 'n' key, errorlevel will be set to 2 and away will not be run. This should get you started. There are some other examples in this document as well as in the file EXAMPLE.BAT (which you can run). 2. REFERENCE 2.1 Introduction ASK is a program for you to use in a batch file to ask for one- key responses from the user. ASK then sets the errorlevel according to the key pressed. The errorlevel can be tested in a batch file to branch to different places. This allows you to ask simple questions like the Yes-or-No type, or to set up a menu- driven batch file. ASK also accepts options like no echo, time out, flush type-ahead. 2.2 Syntax ASK [Options] [Prompt] [Expected Keys] 2.2.1 Prompt [Prompt] is the question to be displayed. It is a "quoted string" (double quotes only). You can embbed double quotes in the prompt by using \" (backslash-quote). If you do not supply [Prompt], ASK will use the default '? '. If you want an empty prompt, use "". 2.2.2 [Expected Keys] [Expected Keys] is a string of all the different keys that the user may press in response to your question. There is no need to quote this string unless you want to include a space in it. Another way to include a space is to use '\ ' (blackslash-space). If the user presses the first key listed in the [Expected Keys], the errorlevel will be set to 1; if the user presses the second key in the [Expected Keys], the errorlevel will be set to 2, and so on. If the user presses a key that is not in the [Expected Keys], ASK will beep and prompt him again until he gets it right. You can override this action with the /q option. If the [Expected Keys] string is not present, the errorlevel will be set to the character code of the key the user pressed. By default, lower case letters will be mapped to the upper case counterpart, i.e. letters always return 65-90. You can disable this mapping with the /c option. If there is no [Expected Keys] and the user presses a key that maps to an extended ASCII, ASK returns 0 (zero). The only way to match a function key is to list that key in [Expected Keys]. When testing errorlevel, be sure to test for the highest number first because if errorlevel 5 means if errorlevel equal to or greater than 5. 2.3 Options Options are used to change the behavior of ASK somewhat. The option letters themselves are not case sensitive so you can use either upper or lower case. /F - flush all keys type-ahead before accepting input /E - no echo. Accept input but do not echo it to the screen. The cursor is also turned off during input. /Q - be quiet, don't yell at the user for invalid response, but return 0 as the errorlevel. This option is meaningless if there is no [Expected Keys]. This is normally used when you want to trap invalid responses and print your own error message instead of using the built-in one. /C - make [Expected Keys] case sensitive. This means letters pressed by the user will only match letters in the same case in [Expected Keys]. If there is no [Expected Keys], then UPPER case letters will return errorlevel 65-90, and lower case letters will return 97-122. /Sxxx - timeout after xxx seconds and return errorlevel 255. xxx can be from 1 to 3 digits and range from 0 to 999. If you supply 0 (zero) as the timeout value, ASK will check the keyboard buffer once before it times out. If there is a key in the buffer (typed ahead), ASK will read it. If you do not supply any value, ASK will time out immediately without even checking type-ahead keys in the keyboard buffer. You can use ASK this way as an alternative to DOS' ECHO command. The advantage is that you can use ASK to print control characters. E.g. ask/s "\e" > E.TXT will put the escape character in the file E.TXT. If more than one timeout option is given, the effect is cumulative. Accuracy is from +0 to -1 second. So if you say s10 it would delay from 9 to 10 seconds. When ASK times out it will not print a linefeed so that the next thing you ECHO will appear immediately after the [prompt]. I usually print *TIMEOUT* so if a user is watching he will understand why things are happening even though he didn't press any key. /Myyy - timeout after yyy minutes and return errorlevel 255. yyy can be from 1 to 3 digits and range from 0 to 999. See the /S option for other details. More than one option letter can share a common switch, like this: ask /QS50C "Blah Blah? " ask/qcm5 "Blah Blah? " ask /c/s9/q "Blah Blah ?" 2.4 Special Characters Characters that you normally cannot put on a command line (e.g. carriage return, escape, backspace, ...) can be included in either [Prompt] or [Expected Keys] using the following conventions: \nnn - translates to ASCII nnn where nnn is a 3-digit decimal number. If this is not followed by another digit then you don't need to put down all three digits. If it is followed by a digit, then you have to put down all three digits (add leading zeros if necessary). For example: ASK "\7HI: " prints a beep and "HI: " ASK "\0070 HI: " prints a beep and "0 HI:" ASK "\070 HI: " prints "F HI: " \e - the escape character. This is equivalent to \27, \027, or \E. \\ - the \ (backslash) character itself \" - the double quote character (without the backslash it will be interpreted as the beginning or the end of a quoted string). \~ - the tilde character itself. ~a - translates to control-a. This works when 'a' is from ASCII 64 to 95 (which produce ASCII 0 thru 31) or is a lower case letter. ~(X) - interpret this as a function key. X is the label on the function key. E.g. ~(f1) refers to the key (F1), ~(ins) refers to the (Ins) key. The label is not case sensitive, so you can use upper or lower case. So ~(F1), ~(INS) would also work. You can use the prefixes S-, C-, and A- with the labels to denote Shift-, Ctrl-, and Alt- version of the key, like ~(s-f1), ~(c-f1), and ~(a-f1). This notation is only recognized in [Expected Keys] and not in [Prompt], because function keys cannot be printed. Here's some examples on using special characters: ask "How \"are\" you?" - will produce How "are" you? ask "Hi?\7" - will produce Hi?*BEEP* ask "Hi?~g" - will also produce Hi?*BEEP* ask "hi" ~m - will let the user use the enter key as a valid response ask "Press (F1)" ~(f1) - wait for user to press the (F1) key If you want to use function keys, you should know that not all keys have a Shift-, Alt-, or Ctrl- version. For instance, Ctrl- Del produces nothing. If you are not sure what a certain combination will produce, let ASK help you. Simply type ask and press the key in question. ASK will echo the key you just pressed. If you press Ctrl-PgUp, you'll see this: ? (C-PgUp) The '?' is the default prompt provided by ASK because you didn't supply one. The (C-PgUp) is the echo of the key you just pressed. Now you know you can use ~(c-pgup) in the [Expected Keys] to match this key. If you had pressed Ctrl-Del, the effect is like you didn't press any keys. The errorlevel is set to 0 for an extended ASCII if no [Expected Keys] is supplied, like in this case. 2.5 Other use You can use ask for many other purposes: 1) As an ECHO command that lets you print control characters. E.g. ask/s \7beep! 2) As a delay command. E.g. ask/m60 > nul (delay 60 minutes). 3) As a PAUSE command with your own prompt. E.g. ask/e "Wake me up when ready ..." 4) Used it to flush type-ahead in a batch file before running another program. E.g. ask/fs These usages might not seem very useful, but they might inspire you to think of something useful. 3. EXAMPLE Here are some examples on how you could use ASK to improve your life. If many people use your computer and say a new version of EDLIN just arrived, you can name the old one EDLIN1 and name the new one EDLIN2, and put the following in EDLIN.BAT: echo off echo "(F1) EDLIN old version" echo "(F2) EDLIN new version" ask/e "Choose one - Press (F1) or (F2)" ~(f1)~(f2) if errorlevel 2 goto new edlin1 %1 goto end :new edlin2 %1 :end When people entered EDLIN, they'll run this batch file and be given a choice of which version to use. This way you don't have to tell everybody that a new version of EDLIN is installed. Here's an example that allows the user to indicate the default response by hitting the Enter key: echo off ask "Should I do it or not (Y/N) [default Y]? " \13yn rem ** errorlevel = 3 means n key rem ** errorlevel = 2 means y key rem ** errorlevel = 1 means return key if errorlevel 3 goto no DoIt :no Now if the user press the Enter key, the computer will DoIt. Note that \013 can be abbreviated as \13 when it is not followed by another numeric character. I like to run chkdsk once in a while but if I don't put it in the AUTOEXEC>BAT file I'll forget to run it. On the other hand, I don't want to run it every time I boot because it takes a while. So I put this in my autoexec.bat: echo off ask/s30 "Run chkdsk (y/n) [n]? " yn~m if not error 255 goto timein echo *TIMEOUT* echo Running chkdsk. Take your time in the bathroom. goto chkdsk :timein if errorlevel 2 goto nocheck :chkdsk chkdsk :nocheck Normally when I boot the computer I'll just hit Enter to the "Run chkdsk" question to skip chkdsk. But sometimes I'll turn on the machine and go to the bathroom. In that case ASK will time out after 30 seconds and start running chkdsk. By the time I come back from the bathroom chkdsk will be done and I've wasted no time. In this case, I'll see this on the screen when ASK times out: Run chkdsk (y/n) [n]? *TIMEOUT* Running chkdsk. Take your time in the bathroom. If you use ANSI.SYS or similar screen driver, you can use ASK to set color or screen mode. For example: ask/s "\e[32m" -- set foreground to green To restore your screen to normal white on black, type ask/s \e[0m The quotes can be omitted in this case since there are no spaces in the prompt string. 4. HISTORY The idea for ASK came from a program called BATQUES contributed to the INFO-IBMPC library (an electronic library on the ARPANET) by H. Fischer. The motivation for writing ASK is to avoid the need for an ASCII table (to use BATQUES). This is the second version of ASK (the previous one is ASK.ASM). This version has the following changes/additions: 1) The program is written in C (IBM C 1.0, compatible with MS C 3.0). Using C allows me to add more functions easily at the cost of increased execution code size. But I think it's worth it. 2) There are two special characters: \ (backslash) and ~ (tilde). 3) Support for function keys. 4) New options: time out, no echo, flush type ahead. 5) Comes with a demo batch file. If you are switching to this version from the old version, you have to change the special character from ^ to \ or ~ in your existing batch files that use ASK. 5. AUTHOR Peter Wu Faculty Support Center 1210 W. Dayton Street, B106 University of Wisconsin, Madison Madison, WI 53715 Electronic mail addresses: uucp: ..{seismo|akgua|allegra|harvard|ucbvax}!uwvax!uwmacc!pwu arpa: pwu@unix.macc.wisc.edu bitnet: WU at WISVMACC compuserve: 76377,1332 Feedback, bug-report, and comments are welcome.