Avoiding Unwanted Spaces

Some time back, I created the Adding a Location to the Windows Path blog post to help readers make better use of some of my book examples. Adding a location to the path makes it possible for Windows to locate applications with greater ease. However, that post didn’t make it clear that a space in a path would cause problems. For example, a path such as, C:\Windows; C:\Python33 (note the space) won’t work. In order for the path to work, each individual path must be separated from the others with just a semicolon, such as C:\Windows;C:\Python33. If you’ve added a path to your Windows setup and find that Windows can’t locate the applications you want to use, please check for an unwanted space in the path.

The limitation on using spaces in a path makes sense because you also have to restrict their use at the command line. For example, typing Dir /A D (with a space between the A and the D) will produce an error. In order to obtain the correct results, you must type Dir /AD and press Enter. The reason the space causes a problem is because the command processor treats spaces as a delimiter, a separator between command elements. The space tells the command processor that one element has ended and a new one has started.

Spaces can creep into commands with relative ease. All it takes is a relatively simple tap on the spacebar at the wrong time. In addition, spaces can be hard to spot when you use certain fonts. When working in an editor to create batch files or other permanently stored command forms, always use a mono-space font, such as Courier New, to make spaces easier to spot. The point is to look for unwanted spaces when a command line feature doesn’t work properly and you know you have typed the correct command.

As a reminder from my books, the command line can also be case sensitive in some cases. Make sure you check your commands to ensure they’re formatted correctly. Let me know about your book-specific command line issue at John@JohnMuellerBooks.com.

 

Author: John

John Mueller is a freelance author and technical editor. He has writing in his blood, having produced 99 books and over 600 articles to date. The topics range from networking to artificial intelligence and from database management to heads-down programming. Some of his current books include a Web security book, discussions of how to manage big data using data science, a Windows command -line reference, and a book that shows how to build your own custom PC. His technical editing skills have helped over more than 67 authors refine the content of their manuscripts. John has provided technical editing services to both Data Based Advisor and Coast Compute magazines. He has also contributed articles to magazines such as Software Quality Connection, DevSource, InformIT, SQL Server Professional, Visual C++ Developer, Hard Core Visual Basic, asp.netPRO, Software Test and Performance, and Visual Basic Developer. Be sure to read John’s blog at http://blog.johnmuellerbooks.com/.

When John isn’t working at the computer, you can find him outside in the garden, cutting wood, or generally enjoying nature. John also likes making wine and knitting. When not occupied with anything else, he makes glycerin soap and candles, which comes in handy for gift baskets. You can reach John on the Internet at John@JohnMuellerBooks.com. John is also setting up a website at http://www.johnmuellerbooks.com/. Feel free to take a look and make suggestions on how he can improve it.