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ED(1)                       General Commands Manual                      ED(1)



NAME
       ed, red - text editor

SYNOPSIS
       ed [-GVhs] [-p string] [file]

       red [-GVhs] [-p string] [file]

DESCRIPTION
       ed is a line-oriented text editor.  It is used to create, display, mod-
       ify and otherwise manipulate text files.  red is a  restricted  ed:  it
       can  only  edit files in the current directory and cannot execute shell
       commands.

       If invoked with a file argument, then a copy of file is read  into  the
       editor's  buffer.   Changes  are  made to this copy and not directly to
       file itself.  Upon quitting ed, any changes not explicitly saved   with
       a `w' command are lost.

       Editing  is  done in two distinct modes: command and input.  When first
       invoked, ed is in command mode.  In this mode commands  are  read  from
       the  standard input and executed to manipulate the contents of the edi-
       tor buffer.  A typical command might look like:

              ,s/old/new/g

       which replaces all occurrences of the string old with new.

       When an input command, such  as  `a'  (append),  `i'  (insert)  or  `c'
       (change), is given, ed enters input mode.  This is the primary means of
       adding text to a file.   In  this  mode,  no  commands  are  available;
       instead,  the  standard input is written directly to the editor buffer.
       Lines consist of text up to and including a newline  character.   Input
       mode is terminated by entering a single period  (.) on a line.

       All  ed  commands  operate on whole lines or ranges of lines; e.g., the
       `d' command deletes lines; the `m' command moves lines, and so on.   It
       is possible to modify only a portion of a line by means of replacement,
       as in the example above.  However even here, the `s' command is applied
       to whole lines at a time.

       In  general,  ed  commands consist of zero or more line addresses, fol-
       lowed by a single character command and possibly additional parameters;
       i.e., commands have the structure:

              [address [,address]]command[parameters]

       The  address(es)  indicate the line or range of lines to be affected by
       the command.  If fewer addresses are given than  the  command  accepts,
       then default addresses are supplied.


   OPTIONS
       -G      Forces backwards compatibility.  Affects the commands `G', `V',
               `f', `l', `m', `t', and `!!'.

       -s      Suppresses diagnostics. This should be used  if  ed's  standard
               input is from a script.


       -p string
               Specifies  a  command  prompt.   This may be toggled on and off
               with the `P' command.


       file    Specifies the name of a file to read.  If file is prefixed with
               a bang (!), then it is interpreted as a shell command.  In this
               case, what is read is the standard output of file executed  via
               sh(1).   To  read  a file whose name begins with a bang, prefix
               the name with a backslash (\).  The default filename is set  to
               file only if it is not prefixed with a bang.


   LINE ADDRESSING
       An address represents the number of a line in the buffer.  ed maintains
       a current address which  is  typically  supplied  to  commands  as  the
       default  address  when  none  is specified.  When a file is first read,
       the current address is set to the last line of the file.   In  general,
       the current address is set to the last line affected by a command.

       A  line address is constructed from one of the bases in the list below,
       optionally followed by a numeric offset.  The offset  may  include  any
       combination  of  digits,  operators  (i.e.   +  and  -) and whitespace.
       Addresses are read from left to right, and their  values  are  computed
       relative to the current address.

       One  exception to the rule that addresses represent line numbers is the
       address 0 (zero).  This means "before the first  line,"  and  is  legal
       wherever it makes sense.

       An  address range is two addresses separated either by a comma or semi-
       colon. The value of the first address in  a  range  cannot  exceed  the
       value of the the second.  If only one address is given in a range, then
       the second address is set to the  given  address.   If  an  n-tuple  of
       addresses  is given where n > 2, then the corresponding range is deter-
       mined by the last two addresses in the n-tuple.  If only one address is
       expected, then the last address is used.

       Each  address in a comma-delimited range is interpreted relative to the
       current address.  In a semicolon-delimited range, the first address  is
       used  to set the current address, and the second address is interpreted
       relative to the first.


       The following address symbols are recognized.


       .       The current line (address) in the buffer.


       $       The last line in the buffer.


       n       The nth, line in the buffer where n is a number  in  the  range
               [0,$].


       -       The  previous  line.   This  is  equivalent  to  -1  and may be
               repeated with cumulative effect.


       ^n      The nth previous line, where n is a non-negative number.


       +       The next line.  This is equivalent to +1 and  may  be  repeated
               with cumulative effect.


       whitespace n

       +n      The  nth  next  line, where n is a non-negative number.  White-
               space followed by a number n is interpreted as +n.


       ,       The first through last lines in the buffer.  This is equivalent
               to the address range 1,$.


       ;       The  current through last lines in the buffer.  This is equiva-
               lent to the address range .,$.


       /re/    The next line containing the regular expression re.  The search
               wraps  to the beginning of the buffer and continues down to the
               current line, if necessary.  // repeats the last search.


       ?re?    The previous line containing the regular  expression  re.   The
               search  wraps  to the end of the buffer and continues up to the
               current line, if necessary.  ?? repeats the last search.


       'lc     The line previously marked by a `k' (mark) command, where lc is
               a lower case letter.


   REGULAR EXPRESSIONS
       Regular  expressions are patterns used in selecting text.  For example,
       the ed command

              g/string/

       prints all lines containing string.  Regular expressions are also  used
       by the `s' command for selecting old text to be replaced with new.

       In  addition  to  a specifying string literals, regular expressions can
       represent classes of strings.  Strings thus represented are said to  be
       matched by the corresponding regular expression.  If it is possible for
       a regular expression to match several strings in a line, then the left-
       most longest match is the one selected.

       The following symbols are used in constructing regular expressions:


       c       Any character c not listed below, including `{', '}', `(', `)',
               `<' and `>', matches itself.


       \c      A backslash-escaped character c other than `{', '}', `(',  `)',
               `<', `>', `b', 'B', `w', `W', `+', and `?'  matches itself.


       .       Matches any single character.


       [char-class]
               Matches  any single character in char-class.  To include a  `]'
               in char-class, it must be the  first  character.   A  range  of
               characters may be specified by separating the end characters of
               the range with a `-', e.g.,  `a-z'  specifies  the  lower  case
               characters.  The following literal expressions can also be used
               in char-class to specify sets of characters:

                 [:alnum:]  [:cntrl:]  [:lower:]  [:space:]
                 [:alpha:]  [:digit:]  [:print:]  [:upper:]
                 [:blank:]  [:graph:]  [:punct:]  [:xdigit:]

               If `-' appears as the first or last  character  of  char-class,
               then  it  matches  itself.   All other characters in char-class
               match themselves.

               Patterns in char-class of the form:

                 [.col-elm.] or,   [=col-elm=]

               where col-elm is a collating element are interpreted  according
               to  locale(5)  (not  currently supported).  See regex(3) for an
               explanation of these constructs.

       [^char-class]
               Matches any single character, other than newline, not in  char-
               class.  char-class is defined as above.

       ^       If  `^' is the first character of a regular expression, then it
               anchors the regular expression to  the  beginning  of  a  line.
               Otherwise, it matches itself.

       $       If  `$'  is  the  last  character  of  a regular expression, it
               anchors the regular expression to the end of  a  line.   Other-
               wise, it matches itself.

       \(re\)  Defines a (possibly null) subexpression re.  Subexpressions may
               be nested.  A subsequent backreference of the form `\n',  where
               n  is  a number in the range [1,9], expands to the text matched
               by the nth subexpression.  For example, the regular  expression
               `\(a.c\)\1'  matches  the  string  `abcabc',  but not `abcadc'.
               Subexpressions are ordered relative to their left delimiter.

       *       Matches the single character regular expression  or  subexpres-
               sion  immediately  preceding  it zero or more times.  If '*' is
               the first character of a regular expression  or  subexpression,
               then  it  matches  itself.   The  `*' operator sometimes yields
               unexpected results.  For example, the regular  expression  `b*'
               matches  the  beginning of the string `abbb', as opposed to the
               substring `bbb', since a  null  match  is  the  only  left-most
               match.

       \{n,m\}
       \{n,\}
       \{n\}   Matches  the  single character regular expression or subexpres-
               sion immediately preceding it at least n and at most  m  times.
               If  m  is  omitted,  then  it matches at least n times.  If the
               comma is also omitted, then it matches  exactly  n  times.   If
               any of these forms occurs first in a regular expression or sub-
               expression, then it is interpreted literally (i.e., the regular
               expression `\{2\}' matches the string `{2}', and so on).

       \<
       \>      Anchors  the  single character regular expression or subexpres-
               sion immediately following it to the beginning (\<)  or  ending
               (\>)  of  a  word, i.e., in ASCII, a maximal string of alphanu-
               meric characters, including the underscore (_).


       The following extended operators are preceded by  a  backslash  (\)  to
       distinguish them from traditional ed syntax.

       \`
       \'      Unconditionally  matches the beginning (\`) or ending (\') of a
               line.

       \?      Optionally matches the single character regular  expression  or
               subexpression immediately preceding it.  For example, the regu-
               lar expression `a[bd]\?c' matches the strings `abc', `adc'  and
               `ac'.   If  \? occurs at the beginning of a regular expressions
               or subexpression, then it matches a literal `?'.

       \+      Matches the single character regular expression  or  subexpres-
               sion  immediately preceding it one or more times.  So the regu-
               lar expression `a\+' is shorthand for `aa*'.  If \+  occurs  at
               the beginning of a regular expression or subexpression, then it
               matches a literal `+'.


       \b      Matches the beginning or ending (null string) of a word.   Thus
               the   regular   expression   `\bhello\b'   is   equivalent   to
               `\<hello\>'.  However, `\b\b' is  a  valid  regular  expression
               whereas `\<\>' is not.

       \B      Matches (a null string) inside a word.

       \w      Matches any character in a word.

       \W      Matches any character not in a word.

   COMMANDS
       All  ed  commands are single characters, though some require additional
       parameters.  If a command's parameters extend over several lines,  then
       each line except for the last must be terminated with a backslash (\).

       In  general,  at  most  one command is allowed per line.  However, most
       commands accept a print suffix, which is any of `p' (print), `l' (list)
       , or `n' (enumerate), to print the last line affected by the command.

       An interrupt (typically ^C) has the effect of aborting the current com-
       mand and returning the editor to command mode.

       ed recognizes the following commands.  The commands are shown  together
       with the default address or address range supplied if none is specified
       (in parenthesis).

       (.)a    Appends text to the buffer after the addressed line, which  may
               be  the  address 0 (zero).  Text is entered in input mode.  The
               current address is set to last line entered.

       (.,.)c  Changes lines in the buffer.  The addressed lines  are  deleted
               from  the buffer, and text is appended in their place.  Text is
               entered in input mode.  The current address is set to last line
               entered.

       (.,.)d  Deletes  the  addressed  lines  from the buffer.  If there is a
               line after the deleted range, then the current address  is  set
               to  this line. Otherwise the current address is set to the line
               before the deleted range.

       e file  Edits file, and sets the default  filename.   If  file  is  not
               specified,  then  the   default filename is used.  Any lines in
               the buffer are deleted before the new file is read.   The  cur-
               rent address is set to the last line read.

       e !command
               Edits  the standard output of `!command', (see !command below).
               The default filename is unchanged.  Any lines in the buffer are
               deleted  before  the  output  of  command is read.  The current
               address is set to the last line read.

       E file  Edits file unconditionally.  This is similar to the e  command,
               except  that  unwritten  changes are discarded without warning.
               The current address is set to the last line read.

       f file  Sets the default filename to file.  If file is  not  specified,
               then the default unescaped filename is printed.

       (1,$)g/re/command-list
               Applies  command-list to each of the addressed lines matching a
               regular expression re.  The current address is set to the  line
               currently  matched before command-list is executed.  At the end
               of the `g' command, the current address is set to the last line
               affected by command-list.

               Each  command  in  command-list must be on a separate line, and
               every line except for the last must be terminated  by  a  back-
               slash (\).  Any commands are allowed, except for `g', `G', `v',
               and `V'.  A newline alone in command-list is  equivalent  to  a
               `p' command.

       (1,$)G/re/
               Interactively  edits  the  addressed  lines  matching a regular
               expression re.  For each matching line, the  line  is  printed,
               the current address is set, and the user is prompted to enter a
               command-list.  At the end  of  the  `G'  command,  the  current
               address is set to the last line affected by (the last) command-
               list.

               The format of command-list is the same as that of the `g'  com-
               mand.   A  newline alone acts as a null command list.  A single
               `&' repeats the last non-null command list.

       H       Toggles the printing of error explanations.  By default, expla-
               nations  are  not  printed.   It is recommended that ed scripts
               begin with this command to aid in debugging.

       h       Prints an explanation of the last error.

       (.)i    Inserts text in the buffer before the current  line.   Text  is
               entered  in input mode.  The current address is set to the last
               line entered.

       (.,.+1)j
               Joins the addressed lines.  The  addressed  lines  are  deleted
               from  the buffer and replaced by a single line containing their
               joined text.  The current address is set to the resultant line.

       (.)klc  Marks a line with a lower case letter lc.  The  line  can  then
               be  addressed  as 'lc (i.e., a single quote followed by lc ) in
               subsequent commands.  The mark is not cleared until the line is
               deleted or otherwise modified.

       (.,.)l  Prints  the  addressed  lines unambiguously.  If invoked from a
               terminal, ed pauses at the end of each page until a newline  is
               entered.  The current address is set to the last line printed.

       (.,.)m(.)
               Moves  lines  in  the buffer.  The addressed lines are moved to
               after the right-hand destination  address,  which  may  be  the
               address  0 (zero).  The current address is set to the last line
               moved.

       (.,.)n  Prints the addressed lines along with their line numbers.   The
               current address is set to the last line printed.

       (.,.)p  Prints  the  addressed lines.    If invoked from a terminal, ed
               pauses at the end of each page until a newline is entered.  The
               current address is set to the last line printed.

       P       Toggles  the  command  prompt  on and off.  Unless a prompt was
               specified by with command-line option -p  string,  the  command
               prompt is by default turned off.

       q       Quits ed.

       Q       Quits  ed  unconditionally.   This is similar to the q command,
               except that unwritten changes are discarded without warning.

       ($)r file
               Reads file to after the addressed line.  If file is not  speci-
               fied,  then  the  default  filename  is  used.  If there was no
               default filename prior to the command, then the  default  file-
               name  is  set  to  file.   Otherwise,  the  default filename is
               unchanged.  The current address is set to the last line read.

       ($)r !command
               Reads to after the addressed line the standard output of `!com-
               mand',  (see  the  !command  below).   The  default filename is
               unchanged.  The current address is set to the last line read.

       (.,.)s/re/replacement/
       (.,.)s/re/replacement/g
       (.,.)s/re/replacement/n
               Replaces text in the addressed lines matching a regular expres-
               sion  re with replacement.  By default, only the first match in
               each line is replaced.  If the `g' (global)  suffix  is  given,
               then  every match to be replaced.  The `n' suffix, where n is a
               positive number, causes only the nth match to be replaced.   It
               is  an  error  if  no substitutions are performed on any of the
               addressed lines.  The current address  is  set  the  last  line
               affected.

               re and replacement may be delimited by any character other than
               space and newline (see the `s' command below).  If one  or  two
               of  the last delimiters is omitted, then the last line affected
               is printed as though the print suffix `p' were specified.


               An unescaped `&' in replacement is replaced  by  the  currently
               matched text.  The character sequence `\m', where m is a number
               in the range  [1,9],  is  replaced  by  the  mth  backreference
               expression  of  the matched text.  If replacement consists of a
               single `%', then replacement  from  the  last  substitution  is
               used.   Newlines  may  be  embedded  in replacement if they are
               escaped with a backslash (\).

       (.,.)s  Repeats the last substitution.  This form of  the  `s'  command
               accepts  a  count suffix `n', or any combination of the charac-
               ters `r', `g', and `p'.  If a count suffix `n' is  given,  then
               only the nth match is replaced.  The `r' suffix causes the reg-
               ular expression of the last search to be used  instead  of  the
               that  of  the  last  substitution.   The `g' suffix toggles the
               global suffix of the last substitution.  The `p' suffix toggles
               the print suffix of the last substitution.  The current address
               is set to the last line affected.

       (.,.)t(.)
               Copies (i.e., transfers)  the  addressed  lines  to  after  the
               right-hand  destination  address,  which  may  be the address 0
               (zero).  The current address is set to the last line copied.

       u       Undoes the last command and restores  the  current  address  to
               what  it was before the command.  The global commands `g', `G',
               `v', and `V'.  are treated as a single command by undo.  `u' is
               its own inverse.

       (1,$)v/re/command-list
               Applies  command-list to each of the addressed lines not match-
               ing a regular expression re.  This is similar to the  `g'  com-
               mand.

       (1,$)V/re/
               Interactively  edits the addressed lines not matching a regular
               expression re.  This is similar to the `G' command.

       (1,$)w file
               Writes the addressed lines to file.  Any previous  contents  of
               file is lost without warning.  If there is no default filename,
               then the default filename is  set  to  file,  otherwise  it  is
               unchanged.  If no filename is specified, then the default file-
               name is used.  The current address is unchanged.

       (1,$)wq file
               Writes the addressed lines to file, and  then  executes  a  `q'
               command.

       (1,$)w !command
               Writes the addressed lines to the standard input of `!command',
               (see the !command below).  The  default  filename  and  current
               address are unchanged.

       (1,$)W file
               Appends  the addressed lines to the end of file.  This is simi-
               lar to the `w' command, expect that the  previous  contents  of
               file is not clobbered.  The current address is unchanged.

       (.)x    Copies  (puts)  the  contents  of  the  cut buffer to after the
               addressed line.  The current address is set to  the  last  line
               copied.

       (.,.)y  Copies  (yanks) the addressed lines to the cut buffer.  The cut
               buffer is overwritten by subsequent `y', `s', `j', `d', or  `c'
               commands.  The current address is unchanged.

       (.+1)zn Scrolls  n lines at a time starting at addressed line.  If n is
               not specified, then the current window size is used.  The  cur-
               rent address is set to the last line printed.

       !command
               Executes  command via sh(1).  If the first character of command
               is `!', then it is replaced by text of the previous `!command'.
               ed  does  not  process command for backslash (\) escapes.  How-
               ever, an unescaped `%' is replaced  by  the  default  filename.
               When the shell returns from execution, a `!'  is printed to the
               standard output.  The current line is unchanged.

       (.,.)#  Begins a comment;  the rest of the line, up to  a  newline,  is
               ignored.   If  a line address followed by a semicolon is given,
               then the current address is set to  that  address.   Otherwise,
               the current address is unchanged.

       ($)=    Prints the line number of the addressed line.

       (.+1)newline
               Prints the addressed line, and sets the current address to that
               line.

FILES
       ed.hup  The file to which ed attempts to write the  buffer if the  ter-
               minal hangs up.

SEE ALSO
       vi(1), sed(1), regex(3), sh(1).

       USD:12-13

       B.  W. Kernighan and P. J. Plauger, Software Tools in Pascal , Addison-
       Wesley, 1981.

LIMITATIONS
       ed processes file arguments for backslash escapes, i.e.,   in  a  file-
       name, any characters preceded by a backslash (\) are interpreted liter-
       ally.

       If a text (non-binary) file is not terminated by a  newline  character,
       then  ed  appends  one  on reading/writing it.  In the case of a binary
       file, ed does not append a newline on reading/writing.

       per line overhead: 4 ints

DIAGNOSTICS
       When an error occurs, if ed's input is from a regular file or here doc-
       ument,  then it exits, otherwise it prints a `?' and returns to command
       mode.  An explanation of the last error can be  printed  with  the  `h'
       (help) command.

       Attempting  to  quit  ed or edit another file before writing a modified
       buffer results in an error.  If the command is entered a  second  time,
       it succeeds, but any changes to the buffer are lost.

       ed exits with 0 if no errors occurred; otherwise >0.



                                5 October 2006                           ED(1)