Tuesday, July 29, 2008

Save output of DOS command to variable

What I want to do is something like: set myVar=pwd BASH and other *nix shells allow you to do things like that (yes the syntax is different) and it is built into the shell. I find it unbelievable that it is so difficult in a batch file to save the output of a DOS command to a variable that can be used later in the script. I know you can use redirection to a file, call the file, delete the file, etc, but that just seems really lame. Then I found that the for loop will allow me to do what I want. It is truly a hack, but it does work, and is fairly straight forward. FOR /F "tokens=1 delims=" %%A in ('pwd') do SET myVar=%%A echo %myVar% if you are not in a batch file you can test it using FOR /F "tokens=1 delims=" %A in ('pwd') do SET myVar=%A echo %myVar%
at

36 comments:

  1. AnonymousDecember 8, 2008 at 1:53:00 AM MST

    Thanks, this is very helpful

    ReplyDelete
  2. Brent VDecember 10, 2008 at 1:34:00 PM MST

    Thanks for the feedback! Glad to help.

    Thanks,

    Brent

    ReplyDelete
  3. AnonymousJanuary 14, 2009 at 7:06:00 AM MST

    Wow, that is straight-forward. Albeit lame as all hell that it has to be done that way. You helped me out, thank you.

    ReplyDelete
  4. Brent VJanuary 14, 2009 at 8:06:00 AM MST

    Hi Gregory,

    Yeah... it is a very lame way to have to do it, but I was happy when I figured out that I could at least do it. Thanks for the feedback.

    Brent

    ReplyDelete
  5. AnonymousMarch 3, 2009 at 12:22:00 AM MST

    I must say, good work!

    ReplyDelete
  6. Brent VMarch 3, 2009 at 8:28:00 AM MST

    Anonymous,

    Thank you for the kind feedback. It is always greatly appreciated.

    Thank you,

    Brent

    ReplyDelete
  7. AnonymousMarch 6, 2009 at 4:00:00 PM MST

    Thanx alot, this problem would have ruined my weekend :D

    ReplyDelete
  8. Brent VMarch 6, 2009 at 5:00:00 PM MST

    Martin,

    So glad you found it helpful and allowed you to enjoy your weekend. :D

    Brent

    ReplyDelete
  9. AnonymousApril 30, 2009 at 1:51:00 AM MST

    very very helpful !! thanks a lot.

    ReplyDelete
  10. Brent VApril 30, 2009 at 8:00:00 AM MST

    Anonymous,

    Thank you for the feedback. So glad it helped.

    Brent

    ReplyDelete
  11. AnonymousSeptember 17, 2009 at 11:00:00 AM MST

    Thanks, very cool.

    Now what if your command was a piped command (multi command solution)?

    i.e. systeminfo | find /I "system up time"

    Thanks again...

    ReplyDelete
  12. Brent VSeptember 18, 2009 at 10:12:00 AM MST

    Anonymous,

    That would me nice. :)

    Brent

    ReplyDelete
  13. AnonymousOctober 25, 2009 at 7:21:00 AM MST

    Excellent description (it was good to hear that this really is a hard thing to do in DOS), good solution, and great description of solution (lame but very effective!). Many thanks!!

    ReplyDelete
  14. Brent VOctober 26, 2009 at 8:31:00 AM MST

    Anonymous,

    Agreed, this is definitely a lame solution, but the only one I know of. I was shocked how difficult and feature lacking dos really is.

    Thank you for the feedback.

    Cheers,

    Brent

    ReplyDelete
  15. AnonymousNovember 6, 2009 at 1:57:00 PM MST

    I noticed that if the out has a space in it, it only returns everything before the space. Why is this?

    ReplyDelete
  16. Brent VNovember 10, 2009 at 3:51:00 PM MST

    Hi anonymous,

    I'm not sure what you mean. If I do something that has a space in the output of the command I think it works fine for me, but maybe you can clarify your problem.

    Here is what I tried.

    FOR /F "tokens=1 delims=" %A in ('date /t') do SET myVar=%A

    echo %myVar%

    In my case, I got Tue 11/10/2009 as the output

    I hope this is helpful.

    Brent

    ReplyDelete
  17. VeskoNovember 27, 2009 at 12:51:00 PM MST

    FOR /F "tokens=1 delims=" %%A in ('ping -n 1 www.google.com | find "Reply"') do SET PING=%%A

    gives me that error message:

    | was unexpected at this time.

    ReplyDelete
  18. AnonymousJanuary 12, 2010 at 2:21:00 AM MST

    When you use a pipe you need to prefix it with a caret ^.

    .. %%i in (`wget -q -O- %FEED% ^| sed -n -f rss.sed`) do ..

    but unlike BASH it seems that you can't store multiline variables and are forced to use temp files.

    ReplyDelete
  19. markApril 27, 2010 at 4:20:00 AM MST

    Very useful, thanks a lot!

    ReplyDelete
  20. JoseJune 10, 2010 at 12:19:00 PM MST

    I love you!
    All kidding aside it did help, thank you.

    ReplyDelete
  21. DanielJune 24, 2010 at 4:40:00 PM MST

    I am trying to run:

    FOR /F "tokens=1 delims=" %%A in ('A:\BIN\SED -f A:\IPSCR.SED A:\IP1.TXT') DO SET IPADR=%%A

    in a batch file. I get a syntax error after this runs. The output from A:\BIN\SED -f A:\IPSCR.SED A:\IP1.TXT is 1921684253, so I don't think that's what's causing the problem.

    Does anyone have any ideas?

    ReplyDelete
  22. EricJuly 2, 2010 at 8:36:00 PM MST

    Awesome dude, thanks for the help.

    ReplyDelete
  23. spacemanAugust 11, 2010 at 12:23:00 PM MST

    I often went crazy trying to return a shell command result in a variable (cd, date, ...)
    You provided the cure!
    Thaks a lot!!!

    ReplyDelete
  24. AnonymousSeptember 9, 2010 at 11:20:00 PM MST

    I was ready to use your solution altough I was sure that I've already used a simple set VAR=%ANTOTHERVAR%.
    Then I found it and since your blog is well placed when searching for this problem, I thought I'd better post it here.

    set VAR=%CD%

    Yeah, right, anything but POSIX compatibility... but it works.

    Simon

    ReplyDelete
  25. AnonymousSeptember 16, 2010 at 5:45:00 PM MST

    Using a caret to escape out the pipe was handy info, thankyou!

    ReplyDelete
  26. AnonymousOctober 23, 2010 at 8:29:00 AM MST

    Thank you for sharing!
    Excellent article

    ReplyDelete
  27. AnonymousMay 18, 2011 at 9:40:00 AM MST

    This is an old thread, but THANK YOU!!!!!!!!!!!!!!

    ReplyDelete
  28. AnonymousJuly 27, 2011 at 8:06:00 AM MST

    Thank you! Everything I needed was in here.

    ReplyDelete
  29. AnonymousDecember 1, 2011 at 6:57:00 AM MST

    Hey, Its "Sets" the final line of the "command" you execute when its of multi-line resulting command.

    eg:
    FOR /F "tokens=1 delims=" %A in ('dir') do SET myVar=%A

    Is there a way we can resolve this?

    ReplyDelete
  30. AnonymousDecember 8, 2011 at 2:34:00 AM MST

    Thanks really helpful all of it. Carrot before pipe and all. Thanks a ton

    ReplyDelete
  31. AnonymousDecember 12, 2012 at 11:34:00 AM MST

    The best answer to this is probably to install Cygwin and use bash or ksh.

    ReplyDelete
  32. AnonymousDecember 12, 2012 at 11:34:00 AM MST

    The best answer to this is probably to install Cygwin and use bash or ksh.

    ReplyDelete
  33. HermDecember 12, 2012 at 11:35:00 AM MST

    The best answer to this is probably to install Cygwin and use bash or ksh.

    ReplyDelete
  34. AnonymousJune 12, 2013 at 12:28:00 AM MST

    Thank you! you save me a lot of time!

    PD: it would be nice if you can explain what the for loop is just actually doing and why the trick works :)

    ReplyDelete
  35. AnonymousJuly 31, 2014 at 3:40:00 PM MST

    the output is this:

    ProcessId
    8432

    I am just interested in the second line.

    for /f "tokens=2" %i in

    does not work.
    Please help

    ReplyDelete
  36. AnonymousMarch 15, 2025 at 12:32:00 AM MST

    FWIW, for future people looking to solve this problem in DOS: the syntax presented is Windows cmd.exe, not DOS command.com. There are no straightforward ways to do this in DOS, unlike in NT-based Windows.

    ReplyDelete