ex

EX(1)                            User Commands                           EX(1)



NAME
       ex, edit - text editor

SYNOPSIS
       ex [-c command|+command] [-r [filename]] [-s|-] [-t tagstring]
              [-w size] [-lLRvV] [file ...]

       edit [-c command|+command] [-r [filename]] [-s|-] [-t tagstring]
              [-w size] [-lLRvV] [file ...]

DESCRIPTION
       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.

   File manipulation
       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.

   Exceptional Conditions
       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

              ex -r resume

       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

              ex -r

       will print a list of the files which have been saved for the user.

   Editing modes
       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.

   Command structure
       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 `|'.

   Command addressing
       .                   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.

   Command descriptions
       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.

   Regular expressions
       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.

   Substitute replacement patterns
       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.

   Option descriptions
       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.

ENVIRONMENT VARIABLES
       The following environment variables affect the behaviour of ex:

       COLUMNS
              Overrides the system-supplied number of terminal columns.

       EXINIT Contains commands to execute at editor startup.  If this
              variable is present, the .exrc file in the user's home directory
              is ignored.

       HOME   Used to locate the editor startup file.

       LANG, LC_ALL
              See locale(7).

       LC_CTYPE
              Determines the mapping of bytes to characters, types of
              characters, case conversion and composition of character classes
              in regular expressions.

       LC_MESSAGES
              Sets the language used for diagnostic and informal messages.

       LINES  Overrides the system-supplied number of terminal lines.

       NLSPATH
              See catopen(3).

       SHELL  The program file used to execute external commands.

       TERM   Determines the terminal type.

FILES
       /usr/lib/ex/expreserve
              preserve command

       /usr/lib/ex/exrecover
              recover command

       /etc/termcap
              describes capabilities of terminals

       $HOME/.exrc
              editor startup file

       /var/tmp/Exnnnnnnnnnn
              editor temporary

       /var/tmp/Rxnnnnnnnnnn
              named buffer temporary

       /var/lib/ex
              preservation directory

DOCUMENTATION
       The document Edit: A tutorial (USD:14) provides a comprehensive
       introduction to edit assuming no previous knowledge of computers or the
       UNIX system.

       The Ex Reference Manual – Version 3.7 (USD:16) is a comprehensive and
       complete manual for the command mode features of ex.  The USAGE section
       of this page is taken from the manual.  For an introduction to more
       advanced forms of editing using the command mode of ex see the editing
       documents written by Brian Kernighan for the editor ed; the material in
       the introductory and advanced documents works also with ex.

       An Introduction to Display Editing with Vi (USD:15) introduces the
       display editor vi and provides reference material on vi.  (This
       reference now forms the vi(1) manual page).  In addition, the Vi Quick
       Reference card summarizes the commands of vi in a useful, functional
       way, and is useful with the Introduction.

SEE ALSO
       awk(1), ed(1), grep(1), sed(1), grep(1), vi(1), catopen(3), termcap(5),
       environ(7), locale(7), regex(7)

AUTHOR
       Originally written by William Joy.

       Mark Horton has maintained the editor since version 2.7, adding macros,
       support for many unusual terminals, and other features such as word
       abbreviation mode.

       This version incorporates changes by Gunnar Ritter.

NOTES
       Undo never clears the buffer modified condition.

       The z command prints a number of logical rather than physical lines.
       More than a screen full of output may result if long lines are present.

       File input/output errors don't print a name if the command line `-'
       option is used.

       The editor does not warn if text is placed in named buffers and not
       used before exiting the editor.

       Null (00) characters are converted to 0200 characters when reading
       input files, and cannot appear in resultant files.

       LC_COLLATE locales are ignored; collating symbols `[.c.]'  and
       equivalence classes `[=c=]' in bracket expressions are recognized but
       useless since `c' is restricted to a single character and is the only
       character matched; range expressions `[a-m]' are always evaluated in
       byte order.



Ancient Unix Ports                  12/1/04                              EX(1)