Ex is the root of a family of editors: edit,
ex and vi. Ex is a superset of ed, with the most
notable extension being a display editing facility. Display based editing on
CRT terminals is the focus of vi.
For those who have not used ed, or for casual users, the
editor edit may be convenient. It avoids some of the complexities of
ex used mostly by systems programmers and persons very familiar with
ed.
The following options are accepted:
- -c command or
+command
- Execute command when editing begins.
- -l
- Start in a special mode useful for the Lisp programming
language.
- -r [filename]
or -L
- When no argument is supplied with this option, all files to be recovered
are listed and the editor exits immediately. If a filename is
specified, the corresponding temporary file is opened in recovery
mode.
- -R
- Files are opened read-only when this option is given.
- -s or -
- Script mode; all feedback for interactive editing is disabled.
EXINIT and .exrc files are not processed.
- -t tagstring
- Read the tags file, then choose the file and position specified by
tagstring for editing.
- -v
- Start in visual mode even if called as ex.
- -V
- Echo command input to standard error, unless it originates from a
terminal.
- -w size
- Specify the size of the editing window for visual mode.
Ex is normally editing the contents of a single file, whose
name is recorded in the current file name. Ex performs all
editing actions in a buffer (actually a temporary file) into which the text
of the file is initially read. Changes made to the buffer have no effect on
the file being edited unless and until the buffer contents are written out
to the file with a write command. After the buffer contents are
written, the previous contents of the written file are no longer accessible.
When a file is edited, its name becomes the current file name, and its
contents are read into the buffer.
The current file is almost always considered to be edited.
This means that the contents of the buffer are logically connected with the
current file name, so that writing the current buffer contents onto that
file, even if it exists, is a reasonable action. If the current file is not
edited then ex will not normally write on it if it already
exists.
For saving blocks of text while editing, and especially when
editing more than one file, ex has a group of named buffers. These
are similar to the normal buffer, except that only a limited number of
operations are available on them. The buffers have names a through
z.
When errors occur ex (optionally) rings the terminal bell
and, in any case, prints an error diagnostic. If the primary input is from a
file, editor processing will terminate. If an interrupt signal is received,
ex prints “Interrupt” and returns to its command level.
If the primary input is a file, then ex will exit when this
occurs.
If a hangup signal is received and the buffer has been modified
since it was last written out, or if the system crashes, either the editor
(in the first case) or the system (after it reboots in the second) will
attempt to preserve the buffer. The next time the user logs in he should be
able to recover the work he was doing, losing at most a few lines of changes
from the last point before the hangup or editor crash. To recover a file one
can use the -r option. If one was editing the file resume,
then he should change to the directory where he were when the crash
occurred, giving the command
After checking that the retrieved file is indeed ok, he can write it over
the previous contents of that file.
The user will normally get mail from the system telling him when a
file has been saved after a crash. The command
will print a list of the files which have been saved for the user.
Ex has five distinct modes. The primary mode is
command mode. Commands are entered in command mode when a `:' prompt
is present, and are executed each time a complete line is sent. In text
input mode ex gathers input lines and places them in the file.
The append, insert, and change commands use text input
mode. No prompt is printed when in text input mode. This mode is left by
typing a `.' alone at the beginning of a line, and command mode
resumes.
The last three modes are open and visual modes,
entered by the commands of the same name, and, within open and visual modes
text insertion mode. Open and visual modes allow local
editing operations to be performed on the text in the file. The open
command displays one line at a time on any terminal while visual
works on CRT terminals with random positioning cursors, using
the screen as a (single) window for file editing changes. These modes are
described (only) in An Introduction to Display Editing with Vi.
Most command names are English words, and initial prefixes of the
words are acceptable abbreviations. The ambiguity of abbreviations is
resolved in favor of the more commonly used commands.
Most commands accept prefix addresses specifying the lines in the
file upon which they are to have effect. The forms of these addresses will
be discussed below. A number of commands also may take a trailing
count specifying the number of lines to be involved in the command.
Thus the command “10p” will print the tenth line in the buffer
while “delete 5” will delete five lines from the buffer,
starting with the current line.
Some commands take other information or parameters, this
information always being given after the command name.
A number of commands have two distinct variants. The variant form
of the command is invoked by placing an `!' immediately after the command
name. Some of the default variants may be controlled by options; in this
case, the `!' serves to toggle the default.
The characters `#', `p' and `l' may be placed after many commands
(A `p' or `l' must be preceded by a blank or tab except in the single
special case `dp'). In this case, the command abbreviated by these
characters is executed after the command completes. Since ex normally
prints the new current line after each change, `p' is rarely necessary. Any
number of `+' or `-' characters may also be given with these flags. If they
appear, the specified offset is applied to the current line value before the
printing command is executed.
It is possible to give editor commands which are ignored. This is
useful when making complex editor scripts for which comments are desired.
The comment character is the double quote: ". Any command line
beginning with " is ignored. Comments beginning with " may also be
placed at the ends of commands, except in cases where they could be confused
as part of text (shell escapes and the substitute and map commands).
More than one command may be placed on a line by separating each
pair of commands by a `|' character. However the global commands,
comments, and the shell escape `!' must be the last command on a line, as
they are not terminated by a `|'.
- .
- The current line. Most commands leave the current line as the last line
which they affect. The default address for most commands is the current
line, thus `.' is rarely used alone as an address.
- n
- The nth line in the editor's buffer, lines being numbered
sequentially from 1.
- $
- The last line in the buffer.
- %
- An abbreviation for “1,$”, the entire buffer.
- +n -n
- An offset relative to the current buffer line. The forms `.+3' `+3' and
`+++' are all equivalent; if the current line is line 100 they all address
line 103.
- /pat/ ?pat?
- Scan forward and backward respectively for a line containing pat, a
regular expression (as defined below). The scans normally wrap around the
end of the buffer. If all that is desired is to print the next line
containing pat, then the trailing / or ? may be
omitted. If pat is omitted or explicitly empty, then the last
regular expression specified is located. The forms \/ and \?
scan using the last regular expression used in a scan; after a substitute
// and ?? would scan using the substitute's regular
expression.
- ´´ ´x
- Before each non-relative motion of the current line `.', the
previous current line is marked with a tag, subsequently referred to as
`´´'. This makes it easy to refer or return to this previous
context. Marks may also be established by the mark command, using
single lower case letters x and the marked lines referred to as
`´x'.
Addresses to commands consist of a series of addressing
primitives, separated by `,' or `;'. Such address lists are evaluated
left-to-right. When addresses are separated by `;' the current line
`.' is set to the value of the previous addressing expression before
the next address is interpreted. If more addresses are given than the
command requires, then all but the last one or two are ignored. If the
command takes two addresses, the first addressed line must precede the
second in the buffer.
Null address specifications are permitted in a list of addresses,
the default in this case is the current line `.'; thus `,100' is equivalent
to `.,100'. It is an error to give a prefix address to a command
which expects none.
The following form is a prototype for all ex commands:
address command ! parameters count flags
All parts are optional; the degenerate case is the empty command which prints
the next line in the file. For sanity with use from within visual mode,
ex ignores a “:” preceding any command.
In the following command descriptions, the default addresses are
shown in parentheses, which are not, however, part of the
command.
- abbreviate
word rhs abbr: ab
- Add the named abbreviation to the current list. When in input mode in
visual, if word is typed as a complete word, it will be changed to
rhs .
( . ) append abbr: a
text
.
Reads the input text and places it after the specified
line. After the command, `.' addresses the last line input or the
specified line if no lines were input. If address `0' is given, text is placed
at the beginning of the buffer.
a!
text
.
The variant flag to append toggles the setting for
the autoindent option during the input of text.
- args
- The members of the argument list are printed, with the current argument
delimited by `[' and `]'.
- cd
directory
- The cd command is a synonym for chdir.
( . , . ) change count abbr: c
text
.
Replaces the specified lines with the input text.
The current line becomes the last line input; if no lines were input it is
left as for a delete.
c!
text
.
The variant toggles autoindent during the
change.
- chdir
directory
- The specified directory becomes the current directory. If no
directory is specified, the current value of the home option is
used as the target directory. After a chdir the current file is not
considered to have been edited so that write restrictions on pre-existing
files apply.
- ( . , . )copy addr flags abbr:
co
- A copy of the specified lines is placed after addr, which
may be `0'. The current line `.' addresses the last line of the
copy. The command t is a synonym for copy.
- ( . , . )delete buffer count
flags abbr: d
- Removes the specified lines from the buffer. The line after the last line
deleted becomes the current line; if the lines deleted were originally at
the end, the new last line becomes the current line. If a named
buffer is specified by giving a letter, then the specified lines
are saved in that buffer, or appended to it if an upper case letter is
used.
edit file abbr: e
ex file
Used to begin an editing session on a new file. The
editor first checks to see if the buffer has been modified since the last
write command was issued. If it has been, a warning is issued and the
command is aborted. The command otherwise deletes the entire contents of the
editor buffer, makes the named file the current file and prints the new
filename. After insuring that this file is sensible (i.e., that it is not a
binary file such as a directory, a block or character special file other than
/dev/tty, a terminal, or a binary or executable file), the editor reads
the file into its buffer.
If the read of the file completes without error, the number of
lines and characters read is typed. Any null characters in the file are
discarded. If none of these errors occurred, the file is considered
edited. If the last line of the input file is missing the trailing
newline character, it will be supplied and a complaint will be issued. This
command leaves the current line `.' at the last line read. If
executed from within open or visual, the current line is
initially the first line of the file.
- e! file
- The variant form suppresses the complaint about modifications having been
made and not written from the editor buffer, thus discarding all changes
which have been made before editing the new file.
- e +n
file
- Causes the editor to begin at line n rather than at the last line;
n may also be an editor command containing no spaces, e.g.:
“+/pat”.
- file abbr:
f
- Prints the current file name, whether it has been `[Modified]' since the
last write command, whether it is read only , the current
line, the number of lines in the buffer, and the percentage of the way
through the buffer of the current line. In the rare case that the current
file is `[Not edited]' this is noted also; in this case one has to use the
form w! to write to the file, since the editor is not sure that a
write will not destroy a file unrelated to the current contents of
the buffer.
- file
file
- The current file name is changed to file which is considered `[Not
edited]'.
- ( 1 , $ ) global /pat/ cmds abbr: g
- First marks each line among those specified which matches the given
regular expression. Then the given command list is executed with
`.' initially set to each marked line.
- The command list consists of the remaining commands on the current input
line and may continue to multiple lines by ending all but the last such
line with a `\'. If cmds (and possibly the trailing /
delimiter) is omitted, each line matching pat is printed.
Append, insert, and change commands and associated
input are permitted; the `.' terminating input may be omitted if it
would be on the last line of the command list. Open and
visual commands are permitted in the command list and take input
from the terminal.
- The global command itself may not appear in cmds. The
undo command is also not permitted there, as undo instead
can be used to reverse the entire global command. The options
autoprint and autoindent are inhibited during a
global, (and possibly the trailing / delimiter) and the
value of the report option is temporarily infinite, in deference to
a report for the entire global. Finally, the context mark
`´´' is set to the value of `.' before the global command
begins and is not changed during a global command, except perhaps by an
open or visual within the global.
- g!
/pat/ cmds abbr: v
- The variant form of global runs cmds at each line not
matching pat.
( . )insert abbr: i
text
.
Places the given text before the specified line. The
current line is left at the last line input; if there were none input it is
left at the line before the addressed line. This command differs from
append only in the placement of text.
i!
text
.
The variant toggles autoindent during the
insert.
- ( . , .+1 ) join count flags abbr:
j
- Places the text from a specified range of lines together on one line.
White space is adjusted at each junction to provide at least one blank
character, two if there was a `.' at the end of the line, or none
if the first following character is a `)'. If there is already white space
at the end of the line, then the white space at the start of the next line
will be discarded.
- j!
- The variant causes a simpler join with no white space processing;
the characters in the lines are simply concatenated.
- ( . ) k x
- The k command is a synonym for mark. It does not require a
blank or tab before the following letter.
- ( . , . ) list count flags
- Prints the specified lines in a more unambiguous way: tabs are printed as
`^I' and the end of each line is marked with a trailing `$'. The current
line is left at the last line printed.
- map[!] lhs
rhs
- The map command is used to define macros for use in visual
command mode. Lhs should be a single character, or the sequence
“#n”, for n a digit, referring to function key n.
When this character or function key is typed in visual mode, it
will be as though the corresponding rhs had been typed. On
terminals without function keys, the user can type “#n”. If
the `!' character follows the command name, the mapping is
interpreted in input mode. See section 6.9 of the “Introduction to
Display Editing with Vi” for more details.
- ( . ) mark x
- Gives the specified line mark x, a single lower case letter. The
x must be preceded by a blank or a tab. The addressing form
`´x' then addresses this line. The current line is not affected by
this command.
- ( . , . ) move addr abbr: m
- The move command repositions the specified lines to be after
addr . The first of the moved lines becomes the current line.
- next abbr:
n
- The next file from the command line argument list is edited.
- n!
- The variant suppresses warnings about the modifications to the buffer not
having been written out, discarding (irretrievably) any changes which may
have been made.
n filelist
n +command filelist
The specified filelist is expanded and the
resulting list replaces the current argument list; the first file in the new
list is then edited. If command is given (it must contain no spaces),
then it is executed after editing the first such file.
- ( . , . ) number count flags abbr:
# or nu
- Prints each specified line preceded by its buffer line number. The current
line is left at the last line printed.
( . ) open flags abbr: o
( . ) open /pat/ flags
Enters intraline editing open mode at each
addressed line. If pat is given, then the cursor will be placed
initially at the beginning of the string matched by the pattern. To exit this
mode use Q. See An Introduction to Display Editing with Vi for more
details.
- preserve
- The current editor buffer is saved as though the system had just crashed.
This command is for use only in emergencies when a write command
has resulted in an error.
- ( . , . )print count abbr: p or
P
- Prints the specified lines with non-printing characters printed as control
characters `^x'; delete (octal 177) is represented as `^?'. The
current line is left at the last line printed.
- ( . )put buffer abbr: pu
- Puts back previously deleted or yanked lines. Normally used
with delete to effect movement of lines, or with yank to
effect duplication of lines. If no buffer is specified, then the
last deleted or yanked text is restored. But no modifying
commands may intervene between the delete or yank and the
put, nor may lines be moved between files without using a named
buffer. By using a named buffer, text may be restored that was saved there
at any previous time.
- quit abbr:
q
- Causes ex to terminate. No automatic write of the editor buffer to
a file is performed. However, ex issues a warning message if the
file has changed since the last write command was issued, and does
not quit. Ex will also issue a diagnostic if there are more
files in the argument list. Normally, the user will wish to save his
changes, and he should give a write command; if he wishes to
discard them, he should the q! command variant.
- q!
- Quits from the editor, discarding changes to the buffer without
complaint.
- ( . ) read file abbr: r
- Places a copy of the text of the given file in the editing buffer after
the specified line. If no file is given the current file name is
used. The current file name is not changed unless there is none in which
case file becomes the current name. The sensibility restrictions
for the edit command apply here also. If the file buffer is empty
and there is no current name then ex treats this as an edit
command.
- Address `0' is legal for this command and causes the file to be read at
the beginning of the buffer. Statistics are given as for the edit
command when the read successfully terminates. After a read
the current line is the last line read. Within open and
visual the current line is set to the first line read rather than
the last.
- ( . ) read !command
- Reads the output of the command command into the buffer after the
specified line. This is not a variant form of the command, rather a read
specifying a command rather than a filename; a blank or tab
before the ! is mandatory.
- recover
file
- Recovers file from the system save area. Used after a accidental
hangup of the phone or a system crash or preserve command. Except
when preserve is used, the user will be notified by mail when a
file is saved.
- rewind abbr:
rew
- The argument list is rewound, and the first file in the list is
edited.
- rew!
- Rewinds the argument list discarding any changes made to the current
buffer.
- set
parameter
- With no arguments, prints those options whose values have been changed
from their defaults; with parameter all it prints all of the option
values.
- Giving an option name followed by a `?' causes the current value of that
option to be printed. The `?' is unnecessary unless the option is Boolean
valued. Boolean options are given values either by the form `set
option' to turn them on or `set nooption' to turn them off;
string and numeric options are assigned via the form `set
option=value'.
- More than one parameter may be given to set ; they are interpreted
left-to-right.
- A list of options can be found below.
- shell abbr:
sh
- A new shell is created. When it terminates, editing resumes.
- source
file abbr: so
- Reads and executes commands from the specified file. Source
commands may be nested.
( . , . ) substitute /pat/repl/ options count flags
abbr:
s
On each specified line, the first instance of pattern
pat is replaced by
replacement pattern
repl. If the
global indicator option
character `g' appears, then all instances are substituted; if the
confirm indication character `c' appears, then before each substitution
the line to be substituted is typed with the string to be substituted marked
with `^' characters. By typing an `y' one can cause the substitution to be
performed, any other input causes no change to take place. After a
substitute the current line is the last line substituted.
Lines may be split by substituting new-line characters into them.
The newline in repl must be escaped by preceding it with a `\'. Other
metacharacters available in pat and repl are described
below.
- stop
- Suspends the editor, returning control to the top level shell. If
autowrite is set and there are unsaved changes, a write is done
first unless the form stop ! is used. This commands is only
available where supported by the teletype driver, shell and operating
system.
- ( . , . ) substitute options count
flags abbr: s
- If pat and repl are omitted, then the last substitution is
repeated. This is a synonym for the & command.
- ( . , . ) t addr flags
- The t command is a synonym for copy .
- ta tag
- The focus of editing switches to the location of tag, switching to
a different line in the current file where it is defined, or if necessary
to another file.
- The tags file is normally created by a program such as ctags, and
consists of a number of lines with three fields separated by blanks or
tabs. The first field gives the name of the tag, the second the name of
the file where the tag resides, and the third gives an addressing form
which can be used by the editor to find the tag; this field is usually a
contextual scan using `/pat/' to be immune to minor changes in the
file. Such scans are always performed as if nomagic was set.
- The tag names in the tags file must be sorted alphabetically.
- unabbreviate
word abbr: una
- Delete word from the list of abbreviations.
- undo abbr:
u
- Reverses the changes made in the buffer by the last buffer editing
command. Note that global commands are considered a single command
for the purpose of undo (as are open and visual.)
Also, the commands write and edit which interact with the
file system cannot be undone. Undo is its own inverse.
- Undo always marks the previous value of the current line `.'
as `´´'. After an undo the current line is the first
line restored or the line before the first line deleted if no lines were
restored. For commands with more global effect such as global and
visual the current line regains it's pre-command value after an
undo.
- unmap[!]
lhs
- The macro expansion associated by map for lhs is
removed.
- ( 1 , $ ) v /pat/ cmds
- A synonym for the global command variant g!, running the
specified cmds on each line which does not match pat.
- version abbr:
ve
- Prints the current version number of the editor as well as the date the
editor was last changed.
- ( . ) visual type count flags abbr:
vi
- Enters visual mode at the specified line. Type is optional and may
be `-' , `^' or `.' as in the z command to specify the
placement of the specified line on the screen. By default, if type
is omitted, the specified line is placed as the first on the screen. A
count specifies an initial window size; the default is the value of
the option window. See the document An Introduction to Display
Editing with Vi for more details. To exit this mode, type Q.
visual file
visual +n file
From visual mode, this command is the same as edit.
- ( 1 , $ ) write file abbr: w
- Writes changes made back to file, printing the number of lines and
characters written. Normally file is omitted and the text goes back
where it came from. If a file is specified, then text will be
written to that file. If the file does not exist it is created. The
current file name is changed only if there is no current file name; the
current line is never changed.
- If an error occurs while writing the current and edited file, the
editor considers that there has been “No write since last
change” even if the buffer had not previously been modified.
- ( 1 , $ ) write>> file abbr: w>>
- Writes the buffer contents at the end of an existing file.
- w! name
- Overrides the checking of the normal write command, and will write
to any file which the system permits.
- ( 1 , $ ) w !command
- Writes the specified lines into command. Note the difference
between w! which overrides checks and w !
which writes to a command.
- wq name
- Like a write and then a quit command.
- wq! name
- The variant overrides checking on the sensibility of the write
command, as w! does.
- xit name
- If any changes have been made and not written to any file, writes the
buffer out. Then, in any case, quits.
- ( . , . )yank buffer count abbr:
ya
- Places the specified lines in the named buffer, for later retrieval
via put. If no buffer name is specified, the lines go to a more
volatile place; see the put command description.
- ( .+1 ) z count
- Print the next count lines, default window.
- ( . ) z type count
- Prints a window of text with the specified line at the top. If type
is `-' the line is placed at the bottom; a `.' causes the line to
be placed in the center. A count gives the number of lines to be displayed
rather than double the number specified by the scroll option. On a
CRT the screen is cleared before display begins unless a count which is
less than the screen size is given. The current line is left at the last
line printed. Forms `z=' and `z^' also exist; `z=' places the current line
in the center, surrounds it with lines of `-' characters and leaves the
current line at this line. The form `z^' prints the window before `z-'
would. The characters `+', `^' and `-' may be repeated for cumulative
effect.
- ! command
- The remainder of the line after the `!' character is sent to a shell to be
executed. Within the text of command the characters `%' and `#' are
expanded as in filenames and the character `!' is replaced with the text
of the previous command. Thus, in particular, `!!' repeats the last such
shell escape. If any such expansion is performed, the expanded line will
be echoed. The current line is unchanged by this command.
- If there has been “[No write]” of the buffer contents
since the last change to the editing buffer, then a diagnostic will be
printed before the command is executed as a warning. A single `!' is
printed when the command completes.
- ( addr , addr ) ! command
- Takes the specified address range and supplies it as standard input to
command; the resulting output then replaces the input lines.
- ( $ ) =
- Prints the line number of the addressed line. The current line is
unchanged.
( . , . ) > count flags
( . , . ) < count flags
Perform intelligent shifting on the specified lines;
< shifts left and > shift right. The quantity of shift is
determined by the shiftwidth option and the repetition of the
specification character. Only white space (blanks and tabs) is shifted; no
non-white characters are discarded in a left-shift. The current line becomes
the last line which changed due to the shifting.
- ^D
- An end-of-file from a terminal input scrolls through the file. The
scroll option specifies the size of the scroll, normally a half
screen of text.
( .+1 , .+1 )
( .+1 , .+1 ) |
An address alone causes the addressed lines to be
printed. A blank line prints the next line in the file.
- ( . , . ) & options count
flags
- Repeats the previous substitute command.
- ( . , . ) ~ options count
flags
- Replaces the previous regular expression with the previous replacement
pattern from a substitution.
A regular expression specifies a set of strings of characters. A
member of this set of strings is said to be matched by the regular
expression. Ex remembers two previous regular expressions: the
previous regular expression used in a substitute command and the
previous regular expression used elsewhere (referred to as the previous
scanning regular expression.) The previous regular expression can
always be referred to by a null re, e.g. `//' or `??'.
The following basic constructs are used to construct magic
mode regular expressions.
- char
- An ordinary character matches itself. The characters `^' at the
beginning of a line, `$' at the end of line, `*' as any
character other than the first, `.', `\', `[', and
`~' are not ordinary characters and must be escaped (preceded) by
`\' to be treated as such.
- ^
- At the beginning of a pattern forces the match to succeed only at the
beginning of a line.
- $
- At the end of a regular expression forces the match to succeed only at the
end of the line.
- .
- Matches any single character except the new-line character.
- \<
- Forces the match to occur only at the beginning of a
“variable” or “word”; that is, either at the
beginning of a line, or just before a letter, digit, or underline and
after a character not one of these.
- \>
- Similar to `\<', but matching the end of a “variable” or
“word”, i.e. either the end of the line or before character
which is neither a letter, nor a digit, nor the underline character.
- [string]
- Matches any (single) character in the class defined by string. Most
characters in string define themselves.
A pair of characters separated by `-' in
string defines the set of characters collating between the
specified lower and upper bounds, thus `[a-z]' as a regular expression
matches any (single) ASCII lower-case letter.
If the sequence `[:class:]' appears in
string, where class is one of `alnum', `alpha',
`blank', `cntrl', `digit', `graph',
`lower', `print', `punct', `space',
`upper', `xdigit', or a locale-specific character class, all
characters that belong to the given class are matched. Thus `[[:lower:]]'
matches any lower-case letter, possibly including characters beyond the
scope of ASCII.
If the first character of string is an `^'
then the construct matches those characters which it otherwise would not;
thus `[^a-z]' matches anything but an ASCII lower-case
letter (and of course a newline).
Backslash `\' is interpreted as an escape character. To
place a `\' character in string, write it twice: `\\'; to place any
of the characters `^', `[', or `-' in string, you escape them with
a preceding `\'.
Characters also lose their special meaning by position: `^'
is an ordinary character unless immediately following the initial `[', `]'
is an ordinary character if immediately following the initial `[' (or `^',
if present), and `-' is an ordinary character if placed immediately behind
`[' or `^', or before ']'.
The concatenation of two regular expressions matches the leftmost
and then longest string which can be divided with the first piece matching
the first regular expression and the second piece matching the second.
A regular expression may be enclosed between the sequences
`\(' and `\)', which matches whatever the enclosed expression
matches.
Any of the (single character matching) regular expressions
mentioned above or a regular expression surrounded by `\(' and '\)' may be
followed by the character `*' to form a regular expression which
matches any number of adjacent occurrences (including 0) of characters
matched by the regular expression it follows.
A single character regular expression or a regular expression
surrounded by `\(' and '\)' followed by
`\{m,n\}' matches a sequence of m
through n occurences, inclusive, of the single character expression.
The values of m and n must be non-negative and smaller than
255. The form `\{m\}' matches exactly m
occurences, `\{m,\}' matches at least m
occurences.
The character `~' may be used in a regular expression, and
matches the text which defined the replacement part of the last
substitute command.
The sequence `\n' matches the text that was matched
by the n-th regular subexpression enclosed between `\(' and `\)'
earlier in the expression.
The basic metacharacters for the replacement pattern are
`&', `~', and `#'; the first two of them are given
as `\&' and `\~' when nomagic is set. Each instance
of `&' is replaced by the characters which the regular expression
matched. The metacharacter `~' stands, in the replacement pattern,
for the defining text of the previous replacement pattern. If the entire
replacement pattern is `#', the defining text of the previous
replacement pattern is used.
Other metasequences possible in the replacement pattern are always
introduced by the escaping character `\'. The sequence
`\n' is replaced by the text matched by the n-th
regular subexpression enclosed between `\(' and `\)'. When nested,
parenthesized subexpressions are present, n is determined by counting
occurrences of `\(' starting from the left. The sequences `\u' and
`\l' cause the immediately following character in the replacement to
be converted to upper- or lower-case respectively if this character is a
letter. The sequences `\U' and `\L' turn such conversion on,
either until `\E' or `\e' is encountered, or until the end of
the replacement pattern.
- autoindent,
ai default: noai
- Can be used to ease the preparation of structured program text. At the
beginning of each append , change or insert command
or when a new line is opened or created by an append ,
change , insert , or substitute operation within
open or visual mode, ex looks at the line being
appended after, the first line changed or the line inserted before and
calculates the amount of white space at the start of the line. It then
aligns the cursor at the level of indentation so determined.
- If the user then types lines of text in, they will continue to be
justified at the displayed indenting level. If more white space is typed
at the beginning of a line, the following line will start aligned with the
first non-white character of the previous line. To back the cursor up to
the preceding tab stop one can hit ^D. The tab stops going
backwards are defined at multiples of the shiftwidth option. The
user cannot backspace over the indent, except by sending an
end-of-file with a ^D.
- Specially processed in this mode is a line with no characters added to it,
which turns into a completely blank line (the white space provided for the
autoindent is discarded.) Also specially processed in this mode are
lines beginning with an `^' and immediately followed by a ^D. This
causes the input to be repositioned at the beginning of the line, but
retaining the previous indent for the next line. Similarly, a `0' followed
by a ^D repositions at the beginning but without retaining the
previous indent.
- Autoindent doesn't happen in global commands or when the
input is not a terminal.
- autoprint,
ap default: ap
- Causes the current line to be printed after each delete , copy
, join , move , substitute , t ,
undo or shift command. This has the same effect as supplying a
trailing `p' to each such command. Autoprint is suppressed in
globals, and only applies to the last of many commands on a line.
- autowrite,
aw default: noaw
- Causes the contents of the buffer to be written to the current file if the
user has modified it and gives a next, rewind, stop,
tag, or ! command, or a ^^ (switch files) or
^] (tag goto) command in visual. Note, that the edit
and ex commands do not autowrite. In each case, there is an
equivalent way of switching when autowrite is set to avoid the
autowrite (edit for next , rewind! for .I
rewind , stop! for stop , tag! for tag ,
shell for ! , and :e # and a :ta!
command from within visual).
- beautify,
bf default: nobeautify
- Causes all control characters except tab, newline and form-feed to be
discarded from the input. A complaint is registered the first time a
backspace character is discarded. Beautify does not apply to
command input.
- directory,
dir default: dir=/tmp
- Specifies the directory in which ex places its buffer file. If this
directory in not writable, then the editor will exit abruptly when it
fails to be able to create its buffer there.
- edcompatible default:
noedcompatible
- Causes the presence of absence of g and c suffixes on
substitute commands to be remembered, and to be toggled by repeating the
suffices. The suffix r makes the substitution be as in the ~
command, instead of like &.
- errorbells,
eb default: noeb
- Error messages are preceded by a bell. Bell ringing in open and
visual on errors is not suppressed by setting noeb. If
possible the editor always places the error message in a standout mode of
the terminal (such as inverse video) instead of ringing the bell.
- exrc default:
noexrc
- If set, the current directory is searched for a .exrc file on
startup. If this file is found, its content is treated as ex
commands and executed immediately after the contents of $HOME/.exrc
on startup.
- flash,
fl default: flash
- If the terminal provides the “visual bell” capability, ex
will use it instead of the audible bell if flash is set.
- hardtabs,
ht default: ht=8
- Gives the boundaries on which terminal hardware tabs are set (or on which
the system expands tabs).
- ignorecase,
ic default: noic
- All upper case characters in the text are mapped to lower case in regular
expression matching. In addition, all upper case characters in regular
expressions are mapped to lower case except in character class
specifications.
- lisp default:
nolisp
- Autoindent indents appropriately for lisp code, and the (
) { } [[ and ]] commands in open and visual are
modified to have meaning for lisp.
- list default:
nolist
- All printed lines will be displayed (more) unambiguously, showing tabs and
end-of-lines as in the list command.
- magic default: magic
for ex and vi, Nomagic for edit.
- If nomagic is set, the number of regular expression metacharacters
is greatly reduced, with only `^' and `$' having special effects. In
addition the metacharacters `~' and `&' of the replacement pattern are
treated as normal characters. All the normal metacharacters may be made
magic when nomagic is set by preceding them with a `\'.
- mesg default:
mesg
- Causes write permission to be turned off to the terminal while the user is
in visual mode, if nomesg is set.
- modelines,
ml default: nomodelines
- If modelines is set, then the first 5 lines and the last five lines
of the file will be checked for ex command lines and the comands issued.
To be recognized as a command line, the line must have the string
ex: or vi: in it. This string may be anywhere in the line
and anything after the : is interpeted as editor commands. This
option defaults to off because of unexpected behavior when editting files
such as /etc/passwd.
- number,
nu default: nonumber
- Causes all output lines to be printed with their line numbers. In addition
each input line will be prompted for by supplying the line number it will
have.
- open default:
open
- If noopen, the commands open and visual are not
permitted.
- optimize,
opt default: optimize
- Throughput of text is expedited by setting the terminal to not do
automatic carriage returns when printing more than one (logical) line of
output, greatly speeding output on terminals without addressable cursors
when text with leading white space is printed.
- paragraphs, para default:
para=IPLPPPQPP LIbp
- Specifies the paragraphs for the { and } operations in
open and visual. The pairs of characters in the option's
value are the names of the macros which start paragraphs.
- prompt default:
prompt
- Command mode input is prompted for with a `:'.
- redraw default:
noredraw
- The editor simulates (using great amounts of output), an intelligent
terminal on a dumb terminal (e.g. during insertions in visual the
characters to the right of the cursor position are refreshed as each input
character is typed.) Useful only at very high speed.
- remap default:
remap
- If on, macros are repeatedly tried until they are unchanged. For example,
if o is mapped to O , and O is mapped to I ,
then if remap is set, o will map to I , but if
noremap is set, it will map to O .
- report default:
report=5, 2 for edit.
- Specifies a threshold for feedback from commands. Any command which
modifies more than the specified number of lines will provide feedback as
to the scope of its changes. For commands such as global , open
, undo , and visual which have potentially more far
reaching scope, the net change in the number of lines in the buffer is
presented at the end of the command, subject to this same threshold. Thus
notification is suppressed during a global command on the
individual commands performed.
- scroll default:
scroll=½ window
- Determines the number of logical lines scrolled when an end-of-file is
received from a terminal input in command mode, and the number of lines
printed by a command mode z command (double the value of scroll
).
- sections default:
sections=SHNHH HU
- Specifies the section macros for the [[ and ]] operations in
open and visual. The pairs of characters in the options's
value are the names of the macros which start paragraphs.
- shell,
sh default: sh=/bin/sh
- Gives the path name of the shell forked for the shell escape command `!',
and by the shell command. The default is taken from SHELL in the
environment, if present.
- shiftwidth,
sw default: sw=8
- Gives the width a software tab stop, used in reverse tabbing with
^D when using autoindent to append text, and by the shift
commands.
- showmatch,
sm default: nosm
- In open and visual mode, when a ) or } is
typed, move the cursor to the matching ( or { for one second
if this matching character is on the screen. Extremely useful with
lisp.
- showmode,
smd default: nosmd
- In visual mode, show a description of the current editing mode in
the window's lower right corner.
- slowopen,
slow terminal dependent
- Affects the display algorithm used in visual mode, holding off
display updating during input of new text to improve throughput when the
terminal in use is both slow and unintelligent. See An Introduction to
Display Editing with Vi for more details.
- tabstop, ts default:
ts=8
- The editor expands tabs in the input file to be on tabstop
boundaries for the purposes of display.
- taglength, tl default:
tl=0
- Tags are not significant beyond this many characters. A value of zero (the
default) means that all characters are significant.
- tags default: tags=tags
/usr/lib/tags
- A path of files to be used as tag files for the tag command. A
requested tag is searched for in the specified files, sequentially. By
default, files called tags are searched for in the current
directory and in /usr/lib (a master file for the entire system).
- term from environment
TERM
- The terminal type of the output device.
- terse default:
noterse
- Shorter error diagnostics are produced for the experienced user.
- warn default:
warn
- Warn if there has been `[No write since last change]' before a `!' command
escape.
- window default:
window=speed dependent
- The number of lines in a text window in the visual command. The
default is 8 at slow speeds (600 baud or less), 16 at medium speed (1200
baud), and the full screen (minus one line) at higher speeds.
- w300, w1200, w9600
- These are not true options but set window only if the speed is slow
(300), medium (1200), or high (9600), respectively. They are suitable for
an EXINIT and make it easy to change the 8/16/full screen rule.
- wrapscan,
ws default: ws
- Searches using the regular expressions in addressing will wrap around past
the end of the file.
- wrapmargin,
wm default: wm=0
- Defines a margin for automatic wrapover of text during input in
open and visual modes. See An Introduction to Text
Editing with Vi for details.
- writeany,
wa default: nowa
- Inhibit the checks normally made before write commands, allowing a
write to any file which the system protection mechanism will allow.