Windows command line tips

I use Windows, Mac, and Linux, each for different reasons. When I run Windows, I like to have a shell that works sorta like bash, but doesn’t run in a subsystem. That is, I like to have the utility programs and command editing features that I’m used to from bash on Mac or Linux, but I want to run native Windows code and not a little version of Linux hosted by Windows. [1]

It took a while to find something I’m happy with. It’s easier to find Linux subsystems like Cygwin. But cmder does exactly what I want. It’s a bash-like shell running on Windows. I also use Windows ports of common Unix utilities. Since these are native Windows programs, I can run them and other Windows applications in the same environment. No error messages along the lines of “I know it looks like you’re running Windows, but you’re not really. So you can’t open that Word document.”

I’ve gotten Unix-like utilities for Windows from several sources. GOW (Gnu on Windows) is one source. I’ve also collected utilities from other miscellaneous sources.

Tab completion and file association

There’s one thing that was a little annoying about cmder: tab completion doesn’t work if you want to enter a file name. For example, if you want to open a Word document foo.docx from the basic Windows command prompt cmd.exe, you can type fo followed by the tab key and the file will open if foo.docx is the first file in your working directory that begins with “fo.”

In cmder, tab completion works for programs first, and then for file names. If you type in fo followed by the tab key, cmder will look for an application whose name starts with “fo.” If you wanted to move foo.docx somewhere, you could type mv fo and tab. In this context, cmder knows that “fo” is the beginning of a file name.

On Mac, you use the open command to open a file with its associated application. For example, on the Mac command line you’d type open foo.docx rather than just foo.docx to open the file with Word.

If there were something like open on Windows, then tab completion wold work in cmder. And there is! It’s the start command. In fact, if you’re accustomed to using open on Mac, you could alias start to open on Windows [2]. So in cmder, you can type start fo and hit tab, and get tab completion for the file name.


The command assoc shows you which application is associated with a file extension. (Include the “.” when using this command. So you’d time assoc .docx rather than assoc docx.

You can direct Windows shell output to the clip command to put the output onto the Windows clipboard.

The control command opens the Windows control panel.

This post shows how to have branching logic in an Emacs config file so you can use the same config file across operating systems.

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[1] Usually on Windows I want to run Windows. But if I do want to run Linux without having to go to another machine, I use WSL (Windows Subsystem for Linux) and I can use it from cmder. Since cmder supports multiple tabs, I can have one tab running ordinary cmd.exe and another tab running bash on WSL.

[2] In the directory containing cmder.exe, edit the file config/user-aliases.cmd. Add a line open=start $1.

Searching files on Windows

Searching files on Windows is a pain. The built-in search features don’t find everything. There may be ways to make them work, but I haven’t persisted long enough to make them work.

On Linux, the combination of find, xargs, and grep works well, and sometimes it works on Windows using the GOW or GnuWin port of these tools. Again there may be a way to make the ported utilities work more as expected, though I haven’t found it. I suspect the problem isn’t with the tools per se but their interaction with the command line. I also tried Emacs features like rgrep, but these features use the ported find and grep utilities, and so you run into the same problems with Emacs as you do running them directly and more.

Ack logo

It looks like ack is the way to go. I heard about it a long time ago and kept meaning to try it out. Now I finally did. It’s fast, convenient, etc. But here are the two things I most like about it:

  1. Ack works the same across platforms.
  2. Ack uses Perl regular expression syntax.

While the alternatives above are supposed to work the same across platforms, they don’t in my experience. But ack does because it’s a pure Perl program. All the portability has been delegated to Perl, where it is well handled. I imagine once I become more familiar with ack I’ll prefer it on Linux as well.

Because it’s a Perl program, ack uses Perl regex syntax. Perl has the most powerful regex implementation out there, though I seldom need any features unique to Perl. More important for me is that Perl regular expression dialect is the one I remember most easily.

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For daily tips on regular expressions, follow @RegexTip on Twitter.

Regex tip icon

Remembering COM

In the late ’90s I thought COM (Microsoft’s Component Object Model) was the way of the future. The whole architecture starting with the IUnknown interface was very elegant. And to hear Don Box explain it, COM was almost inevitable.

I was reminded of COM when I saw the slides for Kevlin Henney’s presentation Worse is better, for better or for worse. Henney quotes William Cook’s paper that has this to say about COM:

To me, the prohibition of inspecting the representation of other objects is one of the defining characteristics of object oriented programming.  …

One of the most pure object-oriented programming models yet defined is the Component Object Model (COM). It enforces all of these principles rigorously. Programming in COM is very flexible and powerful as a result.

And yet programming COM was painful. I wondered at the time why something so elegant in theory was so difficult in practice.  I have some ideas on this, but I haven’t thought through them enough to write them down.

Just as I was starting to grok COM, someone from Microsoft told me “COM is dead” and hinted at a whole new approach to software development that would be coming out of Microsoft, what we now call .NET.

COM had some good ideas, and some of these ideas have been reborn in WinRT. I’ve toyed with the idea of a blog post like “Lessons from COM,” but I doubt I’ll ever write that. This post is probably as close as I’ll get.

By the way, this post speaks of COM in the past tense as is conventional: we speak of technologies in the past tense, not when they disappear, but when they become unfashionable. Countless COM objects are running on countless machines, including on Mac and Unix systems, but COM has definitely fallen out of fashion.

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Humbled by a debugging book

I started developing software for Windows in 1995, but I hardly know anything about Windows. I feel like my understanding of Windows peaked around the turn of the millennium and has declined since. I was reminded of the depth of my ignorance by a new book I received recently, Inside Windows Debugging.

This book goes way beyond stepping through code with the Visual Studio debugger. It dives into the architecture of Windows and the details of how different kinds of debugging work: user-mode, kernel-mode, native, managed, remote, etc. It has a little to say about Visual Studio, but focuses on more advanced tools such as WinDbg.

Obviously Inside Windows Debugging is a book about debugging. But it’s also a good book for someone wanting to know more about Windows internals.

WinRT, Projections, and COM

Martyn Lovell gave a great talk on the new Windows Runtime at Lang.NEXT this week. You know it’s going to be a good talk when the speaker uses the word “soporific” four seconds into the presentation.

One of the ideas I found interesting was language projections, providing multiple programming languages idiomatic access to the lowest level system APIs. What’s new is that these projections are not hand-crafted interfaces but software to create interfaces. The operating system calls are described in metadata that the projections use to create language-specific interfaces. This prepares the way for future growth.

In years gone by, Microsoft would first make an API available to C++, then make it available to VB in a later release. But starting with Windows 8, all languages will have immediate access to new features as they are released. Microsoft is writing projections for .NET, JavaScript, and native code. Third parties will write projections for other languages. If an obscure language has a projection, it will gain access to new runtime features at the exact same time that C# does.

Another point I found interesting is that WinRT is reusing some ideas from COM. I thought the basic ideas of COM were brilliant, though in practice COM development was painful. Near the end of the video (42:17), Martyn Lowell explains how WinRT relates to COM.

Philosophically, COM was about taking a world of different languages and using interfaces to abstract them. And we’re about taking a world of different languages [and abstracting them] so in that sense the philosophy is similar. But if you worked with COM at the time, as I did quite a lot, there were a lot of pain points. … The piece of COM that is largely unchanged in Windows Runtime is IUnknown and the marshalling and proxy system. Beyond that, almost everything you can see about the Windows Runtime is about re-imagining an interface-based system …

If COM brings back bad memories, understand that Microsoft is not saying you need to go back to writing COM, only that they’re using ideas from COM to provide you higher-level interfaces.

You can find the talk in various video and audio formats on Channel 9.

Clipboard history

The Windows clipboard only remembers the most recent thing you copied [1]. This can be very disappointing. Maybe you cut a large block of text intending to paste it somewhere, but without thinking you cut something else, and then realize you’ve just wiped out your first cut. Here are a few possible alternatives for Windows, MS Office, and Emacs.

A few years ago I tried ClipX, a free clipboard history manager for Windows, based on Jeff Atwood’s recommendation. It worked OK at first, but then I had problems with it and stopped using it. It looks like the software hasn’t been updated since 2008. If you know of a better alternative, please let me know. Also, please let me know if you have suggestions for Ubuntu.

(Update: See the comments for numerous suggestions of ClipX-like products. Also, see PHenry’s comment about clipboard history in Visual Studio.)

MS Office has its own clipboard that will store 24 entries. It stores things that have been copied either inside or outside of Office applications, but you can only paste from the Office clipboard using an Office application.

Emacs has a “kill ring” which is essentially a clipboard. It also has “registers” which are like named clipboard items.

Yesterday Emacs Knight posted a handy little bit of code for viewing your kill ring.

    (global-set-key "C-cy" '(lambda ()
        (interactive) (popup-menu 'yank-menu)))

If you add this to your .emacs file, you can type ctrl-c y to pull up a little GUI menu displaying the contents of your kill ring.

[1] I’ve heard that Windows actually keeps more clipboard history, but it doesn’t provide a user interface for accessing that history. I don’t know whether this is true. But if it is, you could access the history programmatically. Maybe Office isn’t maintaining its own clipboard but just exposing more of the system clipboard.

Software knowledge shelf life

In my experience, software knowledge has a longer useful shelf life in the Unix world than in the Microsoft world. (In this post Unix is a shorthand for Unix and Linux.)

A pro-Microsoft explanation would say that Microsoft is more progressive, always improving their APIs and tools, and that Unix is stagnant.

A pro-Unix explanation would say that Unix got a lot of things right the first time, that it is more stable, and that Microsoft’s technology turn-over is more churn than progress.

Pick your explanation. But for better or worse, change comes slower on the Unix side. And when it comes, it’s less disruptive.

At least that’s how it seems to me. Although I’ve used Windows and Unix, I’ve done different kinds of work on the two platforms. Maybe the pace of change relates more to the task than the operating system. Also, I have more experience with Windows and so perhaps I’m more aware of the changes there. But nearly everything I knew about Unix 20 years ago is still useful, and much of what I knew about Windows 10 years ago is not.

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Two-finger scrolling on Windows

One of my favorite features of Mac laptops is two-finger scrolling. This lets you scroll down a long document similar to the way the middle wheel does on a Windows mouse.

I mentioned on Twitter this evening that it would be nice if Windows had this feature. Apparently many newer Windows laptops come with this capability. Todd Brooks replied that my laptop might be able to the two-finger scroll if I upgraded my touchpad driver. He was right. I went to the Microsoft Update site and saw that one of the optional updates was exactly what Todd suggested I install.

So far it seems that the two-finger scrolling on my ThinkPad isn’t as smooth as it is on a MacBook Pro, but it’s still nice to have.

Deleting the Windows recycle bin desktop icon

I’ve never kept many icons on my desktop, and tonight I decided to reduce the number to zero. Deleting the recycle bin icon took a little research.

Windows Vista will let you simply delete the recycle bin but other versions of Windows will not.

On Windows 7 you can right-click on the desktop, select Personalize -> Change desktop icons, and uncheck the box for the recycle bin.

On Windows XP, you can edit the registry as described here. The registry changes will take effect next time you log in. [Update: unfortunately the link is no longer available.]

If you don’t want to edit your XP registry, you can right-click on the desktop, select the Arrange Icons By menu, and uncheck the Show Desktop Icons menu. However, this will hide all icons, not just the recycle bin, and will not let you see anything you drag to the desktop until you re-check Show Desktop Icons.

If you miss the recycle bin icon, it’s still in the file explorer on the left side.

Related post: Using Windows without a mouse

Using the Windows file explorer without a mouse

The Windows File Explorer has a number of keyboard shortcuts that do not apply to Windows programs in general.

First of all, you can type Windows key-E to open the File Explorer. You can close it by typing Alt-F4.

Alt-D highlights address box. (Alt-D also highlights the address box of web browsers: IE, Firefox, Safari, etc.) F4 opens a drop-down list of folders in the address bar.

There are several numeric keypad shortcuts for expanding and collapsing folders.

  • * expands everything under the current selection
  • + expands the current selection
  • - collapses the current selection.

Note that the above keys must be on the numeric keypad; the - on the top of the main part of the keyboard, for example, has no effect on the File Explorer.

You can use the up and down arrow keys to move between files and folders.

The right arrow key expands the current selection. If the current selection is already expanded, the key takes you to the first child.

The left arrow key collapses the current selection. If the current selection is already collapsed, the key takes you to the parent folder.

F2 lets you rename an object. (For the rest of this post, “object” means “file or folder.”)

Shift-F10 opens the context menu of an object, as if you had right-clicked on the object. (There’s also a special key for this; the key has a picture of a mouse selecting something from a list.) Once you bring up the context menu, you can use the up and down arrow keys to  highlight a menu item and the enter key to click it.

Alt-Enter opens the Properties dialog for an object, as if you had right-clicked and selected its Properties from the context menu.

F6 lets you cycle between the panes of the File Explorer.

* * *

For daily tips on using Windows without a mouse, you can follow @SansMouse on Twitter or subscribe to its RSS feed. This post will be split into bite size pieces and added to SansMouse a few weeks from now.

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