| MCEDIT(1) | GNU Midnight Commander | MCEDIT(1) |
mcedit - Internal file editor of GNU Midnight Commander.
mcedit [-bcCdfhstVx?] [+lineno] [file1] [file2] ...
mcedit [-bcCdfhstVx?] file1:lineno[:] file2:lineno[:] ...
mcedit is a link to mc, the main GNU Midnight Commander executable. Executing GNU Midnight Commander under this name runs the internal editor and opens files specified on the command line. The editor is based on the terminal version of cooledit - standalone editor for X Window System.
The internal file editor is a full-featured windowed editor. It can edit several files at the same time. Maximum size of each file is 64 megabytes. It is possible to edit binary files. The features it presently supports are: block copy, move, delete, cut, paste; key for key undo; pull-down menus; file insertion; macro commands; regular expression search and replace; shift-arrow text highlighting (if supported by the terminal); insert-overwrite toggle; autoindent; tunable tab size; syntax highlighting for various file types; and an option to pipe text blocks through shell commands like indent and ispell.
Each file is opened in its own window in full-screen mode. Window control in mcedit is similar to the window control in other multi-window program: double click on window title maximizes the window to full-screen or restores window size and position; left-click on window title and mouse drag moves the window in editor area; left-click on low-right frame corner and mouse drag resizes the window. These actions can be made using "Window" menu.
The editor is easy to use and can be used without learning. The pull-down menu is invoked by pressing F9. You can learn other keys from the menu and from the button bar labels.
In addition to that, Shift combined with arrows does text highlighting (if supported by the terminal): Ctrl-Ins copies to the file ~/.cache/mc/mcedit/mcedit.clip, Shift-Ins pastes from ~/.cache/mc/mcedit/mcedit.clip, Shift-Del cuts to ~/.cache/mc/mcedit/mcedit.clip, and Ctrl-Del deletes highlighted text. Mouse highlighting also works on some terminals. To use the standard mouse support provided by your terminal, hold the Shift key. Please note that the mouse support in the terminal doesn't share the clipboard with mcedit.
The completion key (usually Meta-Tab or Escape Tab) completes the word under the cursor using the words used in the file.
To define a macro, press Ctrl-R and then type out the keys you want to be executed. Press Ctrl-R again when finished. The macro can be assigned to any key by pressing that key. The macro is executed when you press the assigned key.
The macro commands are stored in section [editor] it the file ~/.local/share/mc/mc.macros.
External scripts (filters) can be assigned into the any hotkey by edit mc.macros like following:
[editor] ctrl-W=ExecuteScript:25;
This means that ctrl-W hotkey initiates the ExecuteScript(25) action, then editor handler translates this into execution of ~/.local/share/mc/mcedit/macros.d/macro.25.sh shell script.
External scripts are stored in ~/.local/share/mc/mcedit/macros.d/ directory and must be named as macro.XXXX.sh where XXXX is the number from 0 to 9999. See Edit Menu File for more detail about format of the script.
Following macro definition and directives can be used:
Feel free to edit this files, if you need. Here is a sample external script:
l comment selection
TMPFILE=`mktemp ${MC_TMPDIR:-/tmp}/up.XXXXXX` || exit 1
echo #if 0 > $TMPFILE
cat %b >> $TMPFILE
echo #endif >> $TMPFILE
cat $TMPFILE > %b
rm -f $TMPFILE
If some keys don't work, you can use Learn Keys in the Options menu.
mcedit can be used for navigation through code with tags files created by etags or ctags commands. If there is no TAGS file code navigation will not work. For example, in case of exuberant-ctags for C language command will be:
ctags -e --language-force=C -R ./
Meta-Enter shows list box to select item under cursor (cursor should stand at the end of the word).
Meta-Minus where minus is symbol "-" goes to previous function in navigation list (like browser's Back button).
Meta-Equal where equal is symbol "=" goes to next function in navigation list (like browser's Forward button).
mcedit supports syntax highlighting. This means that keywords and contexts (like C comments, string constants, etc) are highlighted in different colors. The following section explains the format of the file ~/.config/mc/mcedit/Syntax. If this file is missing, system-wide /usr/share/mc/syntax/Syntax is used. The file ~/.config/mc/mcedit/Syntax is rescanned on opening of every new editor file. The file contains rules for highlighting, each of which is given on a separate line, and define which keywords will be highlighted with what color.
The file is divided into sections, each beginning with a line with the file command. The sections are normally put into separate files using the include command.
The file command has three arguments. The first argument is a regular expression that is applied to the file name to determine if the following section applies to the file. The second argument is the description of the file type. It is used in cooledit; future versions of mcedit may use it as well. The third optional argument is a regular expression to match the first line of text of the file. The rules in the following section apply if either the file name or the first line of text matches.
A section ends with the start of another section. Each section is divided into contexts, and each context contains rules. A context is a scope within the text that a particular set of rules belongs to. For instance, the text within a C style comment (i.e. between /* and */) has its own color. This is a context, although it has no further rules inside it because there is probably nothing that we want highlighted within a C comment.
A trivial C programming section might look like this:
file .\*\\.c C\sProgram\sFile (#include|/\\\*) wholechars abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_ # default colors define comment brown context default
keyword whole if yellow
keyword whole else yellow
keyword whole for yellow
keyword whole while yellow
keyword whole do yellow
keyword whole switch yellow
keyword whole case yellow
keyword whole static yellow
keyword whole extern yellow
keyword { brightcyan
keyword } brightcyan
keyword '*' green # C comments context /\* \*/ comment # C preprocessor directives context linestart # \n red
keyword \\\n brightred # C string constants context " " green
keyword %d brightgreen
keyword %s brightgreen
keyword %c brightgreen
keyword \\" brightgreen
Each context starts with a line of the form:
context [exclusive] [whole|wholeright|wholeleft] [linestart] delim [linestart] delim [foreground] [background] [attributes]
The first context is an exception. It must start with the command
context default [foreground] [background] [attributes]
otherwise mcedit will report an error. The linestart option specifies that delim must start at the beginning of a line. The whole option tells that delim must be a whole word. To specify that a word must begin on the word boundary only on the left side, you can use the wholeleft option, and similarly a word that must end on the word boundary is specified by wholeright.
The set of characters that constitute a whole word can be changed at any point in the file with the wholechars command. The left and right set of characters can be set separately with
wholechars [left|right] characters
The exclusive option causes the text between the delimiters to be highlighted, but not the delimiters themselves.
Each rule is a line of the form:
keyword [whole|wholeright|wholeleft] [linestart] string foreground [background] [attributes]
Context or keyword strings are interpreted, so that you can include tabs and spaces with the sequences \t and \s. Newlines and backslashes are specified with \n and \\ respectively. Since whitespace is used as a separator, it may not be used as is. Also, \* must be used to specify an asterisk. The * itself is a wildcard that matches any length of characters. For example,
keyword '*' green
colors all C single character constants green. You also could use
keyword "*" green
to color string constants, but the matched string would not be allowed to span across multiple newlines. The wildcard may be used within context delimiters as well, but you cannot have a wildcard as the last or first character.
Important to note is the line
keyword \\\n brightgreen
This line defines a keyword containing the backslash and newline characters. Since the keywords are matched before the context delimiters, this keyword prevents the context from ending at the end of the lines that end in a backslash, thus allowing C preprocessor directive to continue across multiple lines.
The possible colors are: black, gray, red, brightred, green, brightgreen, brown, yellow, blue, brightblue, magenta, brightmagenta, cyan, brightcyan, lightgray and white. The special keyword "default" means the terminal's default. Another special keyword "base" means mc's main colors, it is useful as a placeholder if you want to specify attributes without modifying the background color. When 256 colors are available, they can be specified either as color16 to color255, or as rgb000 to rgb555 and gray0 to gray23.
If the syntax file is shared with cooledit, it is possible to specify different colors for mcedit and cooledit by separating them with a slash, e.g.
keyword #include red/Orange
mcedit uses the color before the slash. See cooledit(1) for supported cooledit colors.
Attributes can be any of bold, italic, underline, reverse and blink, appended by a plus sign if more than one are desired.
Comments may be put on a separate line starting with the hash sign (#).
If you are describing case insensitive language you need to use caseinsensitive directive. It should be specified at the beginning of syntax file.
Because of the simplicity of the implementation, there are a few intricacies that will not be dealt with correctly but these are a minor irritation. On the whole, a broad spectrum of quite complicated situations are handled with these simple rules. It is a good idea to take a look at the syntax file to see some of the nifty tricks you can do with a little imagination. If you cannot get by with the rules I have coded, and you think you have a rule that would be useful, please email me with your request. However, do not ask for regular expression support, because this is flatly impossible.
A useful hint is to work with as much as possible with the things you can do rather than try to do things that this implementation cannot deal with. Also remember that the aim of syntax highlighting is to make programming less prone to error, not to make code look pretty.
The syntax highlighting can be toggled using Ctrl-s shortcut.
The default colors may be changed by appending to the MC_COLOR_TABLE environment variable. Foreground and background colors pairs may be specified for example with:
MC_COLOR_TABLE="$MC_COLOR_TABLE:\ editnormal=lightgray,black:\ editbold=yellow,black:\ editmarked=black,cyan"
Most options can be set from Options dialog box. See the Options menu. The following options are defined in ~/.config/mc/ini and have obvious counterparts in the dialog box. You can modify them to change the editor behavior, by editing the file. Unless specified, a 1 sets the option to on, and a 0 sets it to off, as usual.
The editor also displays non-us characters (160+). When editing binary files, you should set display bits to 7 bits in Midnight Commander's options menu to keep the spacing clean.
/usr/share/mc/help/mc.hlp
/usr/share/mc/mc.ini
/usr/share/mc/mc.lib
/usr/share/mc/syntax/*
~/.config/mc/ini
~/.local/share/mc/mcedit/
This program is distributed under the terms of the GNU General Public License as published by the Free Software Foundation. See the built-in help of Midnight Commander for details on the License and the lack of warranty.
The latest version of this program can be found at http://ftp.midnight-commander.org/.
Paul Sheer (psheer@obsidian.co.za) is the original author of Midnight Commander's internal editor.
Bugs should be reported to http://www.midnight-commander.org/.
| June 2021 | MC Version 4.8.26 |