choice (command)

In computing, choice is a command that allows for batch files to prompt the user to select one item from a set of single-character choices.[1] It is available in a number of operating system command-line shells.

choice
The ReactOS choice command
Developer(s)Microsoft, Novell, Jim Hall, ReactOS Contributors
Initial release1993, 26–27 years ago
Operating systemDOS, Windows, ReactOS
TypeCommand
LicenseMS-DOS, PC DOS, DR-DOS, Windows, PTS-DOS: Proprietary commercial software
FreeDOS, ReactOS: GPL v2
Websitedocs.microsoft.com/en-us/windows-server/administration/windows-commands/choice

History

The command was first introduced as an external command (with filenames CHOICE.COM or CHOICE.EXE) with MS-DOS 6.0.[2] It is included in Novell DOS 7 and IBM PC DOS 7.0, and is also available from the command-line shell of some versions of Microsoft Windows, but not under Windows 2000 and Windows XP.[3] It was first made available for Windows in the Windows XP Resource Kit.[4] It has been reintroduced in Windows Server 2003 and is present in later versions.[5]

Starting with Windows 2000, the SET command has similar functionality using the /P command-line argument. However this command requires an additional key stroke (hitting ENTER key), which is not required by choice.

The choice command has been ported to OS/2, Rexx and Perl.[6] It is also available in FreeDOS,[7] PTS-DOS,[8] and ReactOS.[9] The FreeDOS version was developed by Jim Hall and is licensed under the GPL v2.[10]

Usage

The command returns the selected choice as an exit code which is set to the index of the key that the user selects from the list of choices. The first choice in the list returns a value of 1, the second a value of 2, and so forth. If a key is pressed that is not a valid choice, the command will sound a warning beep. If an error condition is detected, an exit code value of 255 will be returned. An exit code value of 0 will be returned if the user presses CTRL+BREAK or CTRL+C. Choice displays the default choices Y and N if used without parameters.[11]

Syntax

DOS

CHOICE [/C[:]choices] [/N] [/S] [/T[:]c,nn] ["text"]

Arguments:

  • /C[:]choices Specifies allowable keys. The default is "YN".
  • /T[:]c,nn This defaults choice to "c" after "nn" seconds.
  • text Specifies the prompt string to display. (Quotes are optional).

Flags:

  • /N Specifies not to display the choices and "?" at end of prompt string.
  • /S Specifies that choice keys should be treated as case sensitive.

Microsoft Windows, ReactOS

CHOICE [/C [<Choice1><Choice2><…>]] [/N] [/CS] [/T <Timeout> /D <Choice>] [/M <"Text">]

Arguments:

  • /C[:]choices Specifies allowable keys. The default is "YN". (Microsoft Windows restricts valid choice keys to a-z, A-Z, 0-9 and ASCII values of 128 to 254)
  • /T[:]nn This defaults choice to /D after "nn" seconds. Must be specified with default /D.
  • /D[:]c This defaults choice to 'c'.
  • /M text Specifies the prompt string to display.

Flags:

  • /N Specifies not to display the choices and "?" at end of prompt string.
  • /CS Specifies that choice keys should be treated as case sensitive.

Example

The batch file below gives the user three choices.[12] The user is directed depending upon his input by evaluating the exit code using the IF ERRORLEVEL command (which tests on "greater or equal"). The selected choice is then printed to the screen using the ECHO command.

@ECHO off
@CHOICE /C:123
IF ERRORLEVEL 3 GOTO three
IF ERRORLEVEL 2 GOTO two
IF ERRORLEVEL 1 GOTO one
GOTO end
:one
ECHO You have pressed "1"!
GOTO end
:two
ECHO You have pressed "2"!
GOTO end
:three
ECHO You have pressed "3"!
:end
@PAUSE
Note that the example uses the DOS syntax. This example requires slight adjustments before it applies directly to Windows versions of the CHOICE command.
Note that the IF command, when checking the ERRORLEVEL, compares the number and matches if ERRORLEVEL is equal to or higher than that number. Because of this IF ERRORLEVEL comparisons should be done in decrementing order.
Note that if the user presses Control-C to escape CHOICE followed by N then the program will continue. The first "Goto end" is needed.
gollark: ++data get
gollark: ++roll d6
gollark: I roll again to attain skills.
gollark: Too bad.
gollark: ++roll d6

See also

References
  1. Jamsa, Kris A. (1993), DOS: The Complete Reference, Osborne McGraw-Hill, p. 206, ISBN 0078819040.
  2. http://www.computerhope.com/choicehl.htm
  3. Microsoft Windows XP Command-line reference A-Z
  4. Choice - Accept user input - Windows CMD - SS64.com
  5. http://www.techrepublic.com/blog/windows-and-office/make-the-choice-command-work-for-you-even-in-windows-7
  6. http://www.robvanderwoude.com/choice.php
  7. http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.2/repos/pkg-html/group-base.html
  8. "PTS-DOS 2000 Pro User Manual" (PDF). Buggingen, Germany: Paragon Technology GmbH. 1999. Archived (PDF) from the original on 2018-05-12. Retrieved 2018-05-12.
  9. https://github.com/reactos/reactos/blob/master/base/shell/cmd/choice.c
  10. http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.2/repos/pkg-html/choice.html
  11. Microsoft TechNet Choice article
  12. http://www.computerhope.com/batch.htm

Further reading
  • Cooper, Jim (2001). Special Edition Using MS-DOS 6.22, Third Edition. Que Publishing. ISBN 978-0789725738.
  • Stanek, William R. (2008). Windows Command-Line Administrator's Pocket Consultant, 2nd Edition. Microsoft Press. ISBN 978-0735622623.
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