# 1.2. Frequently Asked Questions (FAQ)

## Content

1. Common questions
  1.1. What is Double Commander?
  1.2. What's new in this version?
  1.3. Is it a Total Commander for Linux?
  1.4. What is the difference between this program and my favorite file manager (Total Commander)?
  1.5. I have a 64-bit Operating System. Can I download Double Commander for it?
  1.6. How can I contact the developers of Double Commander?
  1.7. How to update the portable version without losing settings?
2. Issues related to GNU/Linux
  2.1. Which version do I download?
  2.2. Where is the project repository?
  2.3. Plugins from Total Commander do not work?!
  2.4. Can I get access to network resources like in Nautilus or Thunar?
3. Interface configuration
  3.1. How can I change color settings for the panels?
  3.2. What are buttons `R` and `All` in the color settings?
  3.3. Some text in a column overwrites another column's text!
  3.4. How to associate my own icons with some file types?
  3.5. How to create a splitter on the buttons panel?
  3.6. Does DC has other icon themes?
  3.7. How to make function keys and address bar bigger?
  3.8. File panels: how to change the height of elements (strings) and the intervals between them?
4. Issues related to control and navigation
  4.1. Is it possible to automatically move the cursor down one line after selecting using the `Space` key?
  4.2. Is there an ability to create a file operations queue?
  4.3. `Ctrl+A` doesn't work, how to enable it?
  4.4. When all files are selected in a directory, there is no way to deselect them using a mouse.
  4.5. How to create my own context menu in this program?
  4.6. How to customise the context menu, for example, add the item "Open With"?
  4.7. How to automatically unpack and run file from an open archive? It is inconvenient to use the "Unpack and execute" button in the properties window of the packed file every time.
  4.8. Can the comments (via the descript.ion file) be copied/moved when a file is copied/moved from one directory to another?
5. Issues related to the built-in viewer (`F3`) and editor (`F4`)
  5.1. Editor and browser windows appear in random positions, when Compiz is enabled.
  5.2. Internal editor has a strange font – horizontal characters overwrite each other.
  5.3. Viewer does not work with a few images, but works with most.
  5.4. On some text files lines go beyond the window's edge.
  5.5. Can you add column editing feature (like in Notepad++, UltraEdit etc)?
  5.6. Is it possible to add SVG support in the viewer?
  5.7. How can I use regular expressions to search in UTF-8?
  5.8. How to change the syntax highlighting scheme in the internal editor or add new ones?
6. Issues related to the file panels
  6.1. I didn't find a suitable date format for file panels in the list! How to add my own?
  6.2. Is it possible to add SVG thumbnails support in thumbnails view?
  6.3. I want to see the filenames in the "Name" column with extensions, can I do it?
  6.4. Is it possible to sort folders by clicking on column header ("Date", "Size" and so on)?
7. Plugins
  7.1. What does the message "This is not a valid plugin!" mean?
  7.2. ftp.wfx: I try to use FTPS (FTP+SSL), but I get "522 SSL connection failed: session reuse required".
  7.3. ftp.wfx: Does not work with some servers! After connecting, I get errors: "104,Connection reset by peer" and "CSOCK ERROR Connection reset by peer" or "10060,Connection timed out" and "CSOCK ERROR Connection timed out".

## 1. Common questions

Q: What is Double Commander?

A: Double Commander is a cross-platform, twin-panel file manager. Details see here.

Q: What's new in this version?

A: List of changes can be found on the Wiki page. But the project is now under development, so later nightly builds contain many new features and improvements.

Q: Is it a Total Commander for Linux?

A: No, this is another program from other developers. It now supports Windows, GNU/Linux operating systems with toolkits GTK and Qt (depends on Lazarus, so at the moment, GTK2 and Qt5) and macOS(*), also Double Commander is available in the FreeBSD Ports collection.

Q: What is the difference between this program and my favorite file manager (Total Commander)?

A: The goal of the project is to create a program close to TC in operation and with maximum compatibility via the plugins and configuration files. However, Double Commander has some important advantages: it's free to use, works with different operating systems, and is open source.

Q: I have a 64-bit Operating System. Can I download Double Commander for it?

A: Yes, builds for x64 exist under all supported platforms.

Q: How can I contact the developers of Double Commander?

A: The project's official forum or GitHub.
Make sure you are using the latest version of the program and it's a good idea to check the development (alpha) version before reporting a bug or requesting a new feature. Also see #117.

Q: How to update the portable version without losing settings?

A: Upgrading is done by simply unpacking and replacing files, but you should pay attention to the following files:

- `multiarc.ini` – see external archivers;
- `pixmaps.txt` – see Configuration > Options... > Icons > Only standard icons.

If you did not change these settings, then just agree with the replacement of files. Otherwise, compare with yours and copy the changes.

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## 2. Issues related to GNU/Linux

Q: Which version do I download?

A: If you have KDE or LXQt – download a Qt-build; in other cases (Cinnamon, GNOME, LXDE, MATE or Xfce) a build for GTK toolkit. But this is not strict rule.

Q: Where is the project repository?

A: Repositories for GNU/Linux (CentOS, Debian, Fedora, openSUSE, Ubuntu):

- release: GTK2 or Qt5

- alpha ("nightly") build: GTK2 or Qt5

And you can download installation packages DEB or RPM without adding a repository to the system.
Also portable version is available (compiled binaries packed with XZ, use `doublecmd.sh` to launch) or you can download the source code and compile DC for yourself.

Q: Plugins from Total Commander do not work?!

A: They work, but not all of them. Plugins from TC compiled for Windows can only be used with Windows version of Double Commander. But if the plugins have open source code, you can try to build them for GNU/Linux (or maybe ask the plugin developer to do it :)).
There are a number of plugins for Linux and cross-platform plugins (see Wiki, repositories plugins, doublecmd-plugins and others), as well as several topics on the official forum (for example, one, two).

Q: Can I get access to network resources like in Nautilus or Thunar?

A: Yes, DC can use Gvfs. Gvfs supports many protocols: NFS, SMB, FTP, SFTP, WebDAV, MTP, mobile phones (Windows, Android, Apple), media players and other.

First, packages `gvfs` and `gvfs-backends` should be installed (also add `gvfs-fuse`, it can be useful). Keep in mind that some distributions have not packages `gvfs-backends` and `gvfs-fuse`, because they are part of package `gvfs`, or it can be several packages with names `gvfs-backends-*` or `gvfs-*`.

Now insert Gvfs path in the address bar: click by right mouse button at address bar to edit it (or call internal command `cm_EditPath`).

For example, access to

- FTP: `ftp://ftpuser@ftpserver`
- SMB: `smb://servername/sharename/`
- WebDAV: `davs://servername`

Well, for access to FTP (for SSH+SCP too) and SMB you can use default WFX plugins `ftp` and `samba`.

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## 3. Interface configuration

Q: How can I change color settings for the panels?

A: To change the color, you must go to Configurations > Options... > Colors > File panels. These are global settings for both panels and can be overridden, see Configurations > Options... > Files views > Columns > Custom columns.

Q: What are buttons `R` and `All` in the color settings?

A: They are as follows:

- `R` – restore color to the default.

- `All` – apply selected color to all columns.

Q: Some text in a column overwrites another column's text!

A: Configurations > Options... > Files views > Columns, set checkbox "Cut text to column width".

Q: How to associate my own icons with some file types?

A: You must do the following: Configurations > Options... > File associations.

Q: How to create a splitter on the buttons panel?

A: Add a button from the category separator.

Q: Does DC has other icon themes?

A: Now we know only one small theme DoubleMac, but the installation instruction is outdated (see below).
You can make icon theme yourself, it's easy (we will use the name "MyDCTheme" as an example).

How to make:
- open DC folder and see directory structure of "pixmaps/dctheme";
- make copy of "dctheme" with name "mydctheme";
- open "mydctheme/index.theme" and change the theme name: replace "Name=DCTheme" on "Name=MyDCTheme";
- now replace icons.

Notes:
1. Don't use the default icon replacement! Your icons will be replaced after DC update.
2. If you want to keep some existing default icons then just delete them in "mydctheme" and DC will use them from default theme.
3. Some nonstandard icon sizes (such as 40x40, 60x60 and so one) uses for HiDPI monitors.
4. Also see <CustomIcons>.

How to install:

1. Portable version
Copy (or move) your "mydctheme" folder to the "pixmaps" folder near `doublecmd.exe`, restart DC, go to "Configuration" in the main menu > Options... > Icons > Icon theme, choose your theme and restart DC again.

2. Installed version
Go to "Configuration" in the main menu > Options... > Configuration > Directories > Icon themes:, here you will see the list of possible directories.
Don't use /usr/share/doublecmd/pixmaps, C:\Program Files\Double Commander\pixmaps or other system directory: this requires root/admin rights, also this would be a intervention to the packages manager's work in Linux or DC installer for Windows. DC usually suggests the following additional path (besides the "pixmaps" folder near `doublecmd.exe`):

- Windows XP: C:\Documents and Settings\<UserName>\Local Settings\doublecmd\pixmaps
- Windows Vista/7+: C:\Users\<UserName>\AppData\Local\doublecmd\pixmaps
- Unix-like OS: /home/<UserName>/.local/share/doublecmd/pixmaps

If the directory doesn't exist, create it.
Now restart DC, go to "Configuration" in the main menu > Options... > Icons > Icon theme, choose your theme and restart DC again.

Q: How to make function keys and address bar bigger?

A: The size depends on the font size, three ways exists:

1. Simple and fast: you can use `Ctrl`+mouse wheel, it works for the following interface elements or part of DC:
- file list in left and right panels;
- current directory (address) bar;
- function key buttons bar;
- TreeView menu;
- search results in find files dialog;
- internal editor;
- internal viewer (if viewer shows text then this action will change font size, if image then action will work as zoom in/zoom out commands).

2. Go to "Configuration" in the main menu > Options... > Fonts.
Note: All possible are available in version 1.0.0+ only, for 0.9.x and below additionally see the third item.

3. Close DC > open `doublecmd.xml` > find tag `<Fonts></Fonts>` and change `<Size>` of the interface element manually.

Q: File panels: how to change the height of elements (strings) and the intervals between them?

A: The view depends on the following parameters:

- Configuration > Options... > Fonts > Main font
- Configuration > Options... > Icons > Icon size > File panel
- <ExtraLineSpan> (from `<FilesViews>`)

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## 4. Issues related to control and navigation

Q: Is it possible to automatically move the cursor down one line after selecting using the `Space` key?

A: You must do the following: Configurations > Options... > File views > When selecting file with spacebar, move down to next file (as with insert).

Q: Is there an ability to create a file operations queue?

A: A file operations queue was implemented in version 0.4.6 alpha, and was added to the next stable release.

Q: `Ctrl+A` doesn't work, how to enable it?

A: You must do the following: Configurations > Options... > Keys > Hot keys > In the category "Main", scroll to see command `cm_MarkMarkAll` and set `Ctrl+A` shortcut key for it.

Q: When all files are selected in a directory, there is no way to deselect them using a mouse.

A: Several ways:

- Use the ".." item at the beginning of the file list (but if the list of files is long, it will be necessary to scroll it for this).
- Use the main menu: Mark > Unselect All.
- Add the "Unselect All" button (internal command `cm_MarkUnmarkAll`) on the toolbar.
- Go to "Configuration" in the main menu > Options... > Mouse > Selection by mouse > enable "By clicking on icon": the first click will unmark one file, now click on his name. (How to use in thumbnail view, see the description of this parameter.)

Q: How to create my own context menu in this program?

A: Add button to the toolbar of the category "menu". See this section for an example.

Q: How to customize the context menu, for example, add the item "Open With"?

A: This can been incorporated into Double Commander; however, it's easy to add a command to the "Actions" submenu of the context menu. Here is an example of how to open any directory with root privileges:

1. Under File Types, click Add, then enter, e.g. `Dir` in the popup.
2. Under Extensions, click Add, and enter, e.g. `folder` in the popup.
3. Under Actions, click Add, then in the Action: edit line below, enter the action desired, e.g. `Open as root`
4. In the Command edit line, enter the desired command: eg. `pkexec doublecmd %p`
5. After this just right click on any folder, choose "Open as root" and enter root's password. :)

Q: How to automatically unpack and run file from an open archive? It is inconvenient to use the "Unpack and execute" button in the properties window of the packed file every time.

A: See description of <AutoExtractOpenMask>.

Q: can the comments (via the descript.ion file) be copied/moved when a file is copied/moved from one directory to another?

A: Yes, it is possible: go to Configurations > Options > File operations and enable "Process comments with files/folders".

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## 5. Issues related to the built-in viewer (`F3`) and editor (`F4`)

Q: Editor and browser windows appear in random positions, when Compiz is enabled.

A: Edit Compiz settings: place windows > windows with fixed positions and window rules > fixed size windows.

    (class=Doublecmd) & (title=/)

Q: Internal editor has a strange font – horizontal characters overwrite each other.

A: You must use monospace fonts in the viewer and editor.

Q: Viewer does not work with a few images, but works with most.

A: A component used to view the images did not support some JPEG files.

Q: On some text files lines go beyond the window's edge.

A: Use "Show as Wrap text" option in the viewer. Internal editor does not support wrap lines.

Q: Can you add column editing feature (like in Notepad++, UltraEdit etc)?

A: Internal editor supports column and line selection modes and multi-carets, see keyboard shortcuts here.

Q: Is it possible to add SVG support in the viewer?

A: Supported via librsvg:

- Linux: install package `librsvg`.

- Windows: needs `libcairo-2.dll`, `librsvg-2-2.dll` and `libgobject-2.0-0.dll` (+ all dependencies), for example, you can take DLLs from GIMP. You should copy this DLLs to Double Commander folder or in PATH.

Q: How can I use regular expressions to search in UTF-8?

A: This feature has been added to version 1.0.0. Needs PCRE2 library with support 8-bit code units and Unicode support enabled (usually enabled by default):

- Linux: needs `libpcre2-8.so.0`. For example, package `libpcre2-8-0` in Debian/Debian-based distributions or `pcre2` in Arch Linux.

- Windows: needs `libpcre2-8.dll` (by default, the Double Commander distribution contains this DLL).

- macOS(*): needs `libpcre2-8.dylib`.

Q: How to change the syntax highlighting scheme in the internal editor or add new ones?

A: DC uses two components:

1. SynEdit with built-in syntax highlighters. If you want to change any highlighter, you should change the DC or Lazarus source code. But you can easily change the colors used and the file extension lists: go to "Configuration" in the main menu > Options... > Tools > Editor > Highlighters. Do not forget to save customizations for each file type.
All settings are saved in the `highlighters.xml` file.

2. SynUniHighlighter for custom syntax highlighting schemes (*.hgl) and you can try to find or create this files yourself (see below).

This files are usual XML-based files, you can open them in a text editor and read/change. In the beginning of this files is the `<General>` tag (inside `<Info>`):

1) Old format: `<General>` has tags
- `<Name>`: name for the Syntax highlight menu;
- `<FileTypeName>`: list of supported file extensions.

2) New format: `<General>` has attributes
- `Name`: name for the Syntax highlight menu;
- `Extensions`: list of supported file extensions.

(DC supports both formats.)

How to create or edit:

Use UniHighlighter Editor or HglEditor (download). Both programs were written for Windows, but you can use Wine. HglEditor will save HGL-file in the new format.
Two packs of various highlighters are also available.
In the Tools > Editor > Highlighters section, you can change the text and background colors and font style.(Alpha version)

How to add:

1) Portable version
Copy (or move) your HGL-file(s) to the "highlighters" folder near `doublecmd.exe` and restart DC.

2) Installed version
Go to "Configuration" in the main menu > Options... > Configuration > Directories > Highlight:, here you will see the list of possible directories.
Don't use /usr/share/doublecmd/highlighters, C:\Program Files\Double Commander\highlighters or other system directory: this requires root/admin rights, also this would be a intervention to the packages manager's work in Linux or DC installer for Windows. DC usually suggests the following additional path (besides the "highlighters" folder near `doublecmd.exe`):

- Windows XP: C:\Documents and Settings\<UserName>\Local Settings\doublecmd\highlighters
- Windows Vista/7+: C:\Users\<UserName>\AppData\Local\doublecmd\highlighters
- Unix-like OS: /home/<UserName>/.local/share/doublecmd/highlighters

If the directory doesn't exist, create it. Now restart DC.

Additional features:

1) Other submenu

Additional Syntax highlight menu item: if menu is too long then you can move some items to the Other submenu. Just add new attribute `Other` and value 1 to the `<General>` tag and restart DC.
For example, before
`<General Name="AutoIt v3*" Extensions="AU3"/>`
and after
`<General Name="AutoIt v3*" Extensions="AU3" Other="1"/>`

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## 6. Issues related to the file panels

Q: I didn't find a suitable date format for file panels in the list! How to add my own?

A: Date and time format is easy configurable: go to Configurations > Options > Files views > Formatting > Date and time format and use this table.

Q: Is it possible to add SVG thumbnails support in thumbnails view?

A: It's already supported, see Is it possible to add SVG support in the viewer?

Q: I want to see the filenames in the "Name" column with extensions, can I do it?

A: Yes, it's possible. Go to "Configuration" in the main menu > Options... > Files views > Columns > Custom columns, now create a new column set or change existing default set: by default, DC uses `GETFILENAMENOEXT` field for name, use `GETFILENAME` instead.

Q: Is it possible to sort folders by clicking on column header ("Date", "Size" and so on)?

A: Yes, you can enable this feature: go to "Configuration" in the main menu > Options... > Files views > Sorting > Sorting directories and use "sort like files and show first" or "sort like files".

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## 7. Plugins

Q: What does the message "This is not a valid plugin!" mean?

A: This usually means a problem with dependencies: not all required libraries are available in your system. If there are no details in the description of the plugin, could not contact the author or find a solution using search engines, then try the following:

- Windows: FileInfo or PEViewer plugin, utilities such as DLL Export Viewer or Dependency Walker.
- Linux: use terminal and command `ldd` (the easiest way, `ldd pluginname | grep "not found"`), GNU Binutils or AnyELF plugin.

If this is a WDX plugin written in Lua:

1. The Lua library is not available: see DLL required.

2. The script requires an additional module: see the description of the script or contact the author.

3. Error in the script. For debugging, you can use Lua in a terminal or advanced code editor/IDE (for example, ZeroBrane Studio).
If you use the Double Commander functions: create a button with internal command cm_ExecuteScript and use available functions (`DC.LogWrite`, `Dialogs.MessageBox`, `Clipbrd.SetAsText` or save the results to a file).

Q: ftp.wfx: I try to use FTPS (FTP+SSL), but I get "522 SSL connection failed: session reuse required".

A: This server requires session reuse support and `ftp.wfx` supports it, but the OpenSSL libraries are needed: put `libeay32.dll` and `ssleay32.dll` near `doublecmd.exe` or in the PATH.

Q: ftp.wfx: Does not work with some servers! After connecting, I get errors: "104,Connection reset by peer" and "CSOCK ERROR Connection reset by peer" or "10060,Connection timed out" and "CSOCK ERROR Connection timed out".

A: OpenSSL libraries required: put `libeay32.dll` and `ssleay32.dll` near `doublecmd.exe` or in the PATH.

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