NAME
mcedit - Internal file editor of GNU Midnight Commander.
USAGE
mcedit [-bcCdfhstVx?] [+lineno] file
mcedit [-bcCdfhstVx?] file:lineno[:]
DESCRIPTION
mcedit is a link to mc, the main GNU Midnight Commander executable.
Executing GNU Midnight Commander under this name requests staring the
internal editor and opening the file specified on the command line.
The editor is based on the terminal version of cooledit - standalone
editor for X Window System.
OPTIONS
+lineno
Go to the line specified by number (do not put a space between
the + sign and the number).
-b Force black and white display.
-c Force ANSI color mode on terminals that don’t seem to have color
support.
-C <keyword>=<FGcolor>,<BGcolor>:<keyword>= ...
Specify a different color set. See the Colors section in mc(1)
for more information.
-d Disable mouse support.
-f Display the compiled-in search path for GNU Midnight Commander
data files.
-t Force using termcap database instead of terminfo. This option
is only applicable if GNU Midnight Commander was compiled with
S-Lang library with terminfo support.
-V Display the version of the program.
-x Force xterm mode. Used when running on xterm-capable terminals
(two screen modes, and able to send mouse escape sequences).
FEATURES
The internal file editor is a full-featured full screen editor. It can
edit files up to 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 (and our own
scanf-printf search and replace); shift-arrow text highlighting (if
supported by the terminal); insert-overwrite toggle; word wrap;
autoindent; tunable tab size; syntax highlighting for various file
types; and an option to pipe text blocks through shell commands like
indent and ispell.
KEYS
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
~/.mc/cedit/cooledit.clip, Shift-Ins pastes from
~/.mc/cedit/cooledit.clip, Shift-Del cuts to ~/.mc/cedit/cooledit.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 earlier 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. You can then assign
the macro to any key you like by pressing that key. The macro is
executed when you press Ctrl-A and then the assigned key. The macro is
also executed if you press Meta, Ctrl, or Esc and the assigned key,
provided that the key is not used for any other function. The macro
commands are stored in the file ~/.mc/cedit/cooledit.macros. Do NOT
edit this file if you are going to use macros again in the same editing
session, because mcedit caches macro key defines in memory. mcedit now
overwrites a macro if a macro with the same key already exists, so you
won’t have to edit this file. You will also have to restart other
running editors for macros to take effect.
F19 will format C, C++, Java or HTML code when it is highlighted. An
executable file called ~/.mc/cedit/edit.indent.rc will be created for
you from the default template. Feel free to edit it if you need.
C-p will run ispell on a block of text in a similar way. The script
file will be called ~/.mc/cedit/edit.spell.rc.
If some keys don’t work, you can use Learn Keys in the Options menu.
CODE NAVIGATION
mcedit can be used to navigation through code with tags files created
by etags or ctags commands. If there is no file TAGS code navigation
would not work. In example, in case of exuberant-ctags for C language
command will be:
ctags -e --language-force=C -R ./
Meta-Enter show list box to select item under cursor (cusor should
stand at end of word).
Meta-Minus where minus is symbol "-" go to previous function in
navigation list (like a browser Back).
Meta-Equal where equal is symbol "=" go to next function in navigation
list (like a browser Forward).
SYNTAX HIGHLIGHTING
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 ~/.mc/cedit/Syntax. If this file is missing, system-wide
/usr/share/mc/syntax/Syntax is used. The file ~/.mc/cedit/Syntax is
rescanned on opening of a any 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 to 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]
The first context is an exception. It must start with the command
context default [foreground] [background]
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]
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. 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.
Comments may be put on a separate line starting with the hash sign (#).
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.
COLORS
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"
OPTIONS
Most options can now be set from the editors options dialog box. See
the Options menu. The following options are defined in ~/.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 is usual.
use_internal_edit
This option is ignored when invoking mcedit.
editor_tab_spacing
Interpret the tab character as being of this length. Default is
8. You should avoid using other than 8 since most other editors
and text viewers assume a tab spacing of 8. Use
editor_fake_half_tabs to simulate a smaller tab spacing.
editor_fill_tabs_with_spaces
Never insert a tab space. Rather insert spaces (ascii 20h) to
fill to the desired tab size.
editor_return_does_auto_indent
Pressing return will tab across to match the indentation of the
first line above that has text on it.
editor_backspace_through_tabs
Make a single backspace delete all the space to the left margin
if there is no text between the cursor and the left margin.
editor_fake_half_tabs
This will emulate a half tab for those who want to program with
a tab spacing of 4, but do not want the tab size changed from 8
(so that the code will be formatted the same when displayed by
other programs). When editing between text and the left margin,
moving and tabbing will be as though a tab space were 4, while
actually using spaces and normal tabs for an optimal fill. When
editing anywhere else, a normal tab is inserted.
editor_option_save_mode
Possible values 0, 1 and 2. The save mode (see the options menu
also) allows you to change the method of saving a file. Quick
save (0) saves the file by immediately, truncating the disk file
to zero length (i.e. erasing it) and the writing the editor
contents to the file. This method is fast, but dangerous, since
a system error during a file save will leave the file only
partially written, possibly rendering the data irretrievable.
When saving, the safe save (1) option enables creation of a
temporary file into which the file contents are first written.
In the event of an problem, the original file is untouched.
When the temporary file is successfully written, it is renamed
to the name of the original file, thus replacing it. The safest
method is create backups (2). Where a backup file is created
before any changes are made. You can specify your own backup
file extension in the dialog. Note that saving twice will
replace your backup as well as your original file.
editor_word_wrap_line_length
line length to wrap. 72 default.
editor_backup_extension
symbol for add extension to name of backup files. Default "~".
editor_line_state
show state line of editor now it show number of file line (in
future it can show things like folding, breakpoints, etc.). M-n
toglle this option.
editor_visible_spaces
Toggle show visible trailing spaces (TWS), if
editor_visible_spaces=1 TWS showed as ’.’
editor_visible_tabs
Toggle show visible tabs, if editor_visible_tabs=1 tabs showed
as ’<---->’
editor_persistent_selections
Do not remove block selection after moving the cursor.
editor_cursor_beyond_eol
Allow moving cursor beyond the end of line.
editor_syntax_highlighting
enable syntax highlighting.
editor_edit_confirm_save
show confirm dialog on save.
editor_option_typewriter_wrap
to be described
editor_option_auto_para_formatting
to be described
editor_option_save_position
save file position on exit.
source_codepage
symbol representation of codepage name for file (i.e. CP1251, ~
- default).
editor_wordcompletion_collect_entire_file
Search autocomplete candidates in entire of file or just from
begin of file to cursor position (0)
MISCELLANEOUS
You can use scanf search and replace to search and replace a C format
string. First take a look at the sscanf and sprintf man pages to see
what a format string is and how it works. Here’s an example: suppose
that you want to replace all occurrences of an open bracket, three
comma separated numbers, and a close bracket, with the word apples, the
third number, the word oranges and then the second number. You would
fill in the Replace dialog box as follows:
Enter search string
(%d,%d,%d)
Enter replace string
apples %d oranges %d
Enter replacement argument order
3,2
The last line specifies that the third and then the second number are
to be used in place of the first and second.
It is advisable to use this feature with Prompt On Replace on, because
a match is thought to be found whenever the number of arguments found
matches the number given, which is not always a real match. Scanf also
treats whitespace as being elastic. Note that the scanf format %[ is
very useful for scanning strings, and whitespace.
The editor also displays non-us characters (160+). When editing binary
files, you should set display bits to 7 bits in the Midnight Commander
options menu to keep the spacing clean.
FILES
/usr/share/mc/mc.hlp
The help file for the program.
/usr/share/mc/mc.ini
The default system-wide setup for GNU Midnight Commander, used
only if the user’s own ~/.mc/ini file is missing.
/usr/share/mc/mc.lib
Global settings for the Midnight Commander. Settings in this
file affect all users, whether they have ~/.mc/ini or not.
/usr/share/mc/syntax/*
The default system-wide syntax files for mcedit, used only if
the corresponding user’s own ~/.mc/cedit/ file is missing.
$HOME/.mc/ini
User’s own setup. If this file is present then the setup is
loaded from here instead of the system-wide setup file.
$HOME/.mc/cedit/
User’s own directory where block commands are processed and
saved and user’s own syntax files are located.
LICENSE
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 the Midnight Commander for details on the License and the lack
of warranty.
AVAILABILITY
The latest version of this program can be found at
http://midnight-commander.org/.
SEE ALSO
cooledit(1), mc(1), gpm(1), terminfo(1), scanf(3).
AUTHORS
Paul Sheer (psheer@obsidian.co.za) is the original author of the
Midnight Commander’s internal editor.
BUGS
Bugs should be reported to mc-devel@gnome.org