Dealing with quotes in Windows batch scripts

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In a Windows batch file, when you do the following:

set myvar="c:\my music & videos"

the variable myvar is stored with the quotes included. Honestly I find that very stupid. The quotes are just to tell where the string begins and ends, not to be stored as part of the value itself.
How can I prevent this from happening?

Thanks.

7 Answers

It depends on how you want to use the variable. If you just want to use the value of the variable without the quotes you can use either delayed expansion and string substitution, or the for command:

@echo OFF
SETLOCAL enabledelayedexpansion

set myvar="C:\my music & videos"

As andynormancx states, the quotes are needed since the string contains the &. Or you can escape it with the ^, but I think the quotes are a little cleaner.

If you use delayed expansion with string substitution, you get the value of the variable without the quotes:

@echo !myvar:"=!
>>> C:\my music & videos

You can also use the for command:

for /f "tokens=* delims=" %%P in (%myvar%) do (
    @echo %%P
)
>>> C:\my music & videos

However, if you want to use the variable in a command, you must use the quoted value or enclose the value of the variable in quotes:

  1. Using string substitution and delayed expansion to use value of the variable without quotes, but use the variable in a command:

    @echo OFF
    SETLOCAL enabledelayedexpansion
    
    set myvar="C:\my music & videos"
    md %myvar%
    @echo !myvar:"=! created.
    
  2. Using the for command to use the value of the variable without quotes, but you'll have to surround the variable with quotes when using it in commands:

    @echo OFF
    set myvar="C:\my music & videos"
    
    for /f "tokens=* delims=" %%P in (%myvar%) do (
        md "%%P"
        @echo %%P created.
    )
    

Long story short, there's really no clean way to use a path or filename that contains embedded spaces and/or &s in a batch file.

Use jscript.

Many moons ago (i.e. about 8 years give or take) I was working on a large C++/VB6 project, and I had various bits of Batch Script to do parts of the build.

Then someone pointed me at the Joel Test, I was particularly enamoured of point 2, and set about bringing all my little build scripts into one single build script . . .

and it nearly broke my heart, getting all those little scripts working together, on different machines, with slightly different setups, ye Gods it was dreadful - particularly setting variables and parameter passing. It was really brittle, the slightest thing would break it and require 30 minutes of tweaking to get going again.

Eventually - I can be stubborn me - I chucked the whole lot in and in about a day re-wrote it all in JavaScript, running it from the command prompt with CScript.

I haven't looked back. Although these days it's MSBuild and Cruise Control, if I need to do something even slightly involved with a batch script, I use jscript.

Try using the escape character '^', e.g.

set myvar=c:\my music ^& videos

You'll have you be careful when you expand myvar because the shell might not treat the & as a literal. If the above doesn't work, try inserting a caret into the string too:

set myvar=c:\my music ^^^& videos

Two solutions:

  1. Don't use spaces or other characters that are special to the command interpreter in path names (directory or file names). If you use only letters, numbers, underscores, and hyphens (and a period before the extension to identify the file type), your scripting life will become immeasurably simpler.

    I have written and otherwise collected a plethora of tools over the years, including a DOS utility that will rename files. (It began as something that just removed spaces from filenames, but morphed into something that will replace characters or strings within the filenames, even recursively.) If anyone's interested, I will get my long-neglected web site up and running and post this and others.

    That said, variables aren't just for holding pathnames, so...

  2. As others have already pointed out, SET "myvar=c:\my music & videos" is the correct workaround for such a variable value. (Yes, I said workaround. I agree that your initial inclination to just quote the value ("my music & videos") is far more intuitive, but it is what it is, as they say.

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