ed



ED(1)                                                                    ED(1)




NAME

       ed, red - text editor


SYNOPSIS

       ed [-] [-Gs] [-p string] [file]

       red [-] [-Gs] [-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 β€˜€™ 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 occurences of the string old with new.

       When an input command, such  as  β€˜€™  (append),  β€˜€™  (insert)  or  β€˜€™
       (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
       β€˜€™ command deletes lines; the β€˜€™ 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 β€˜€™ 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 β€˜€™, β€˜€™,
               β€˜€™, β€˜€™, β€˜€™, β€˜€™, and β€˜!!’.

       -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 β€˜€™ 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

       ^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.


       +n

       whitespace n
               The  nth  next line, where n is a non-negative number.  Whites-
               pace 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.


       Β΄lc     The line previously marked by a β€˜€™ (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 β€˜€™ 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 β€˜{’, ’}’, β€˜(’, β€˜)’,
               β€˜<’ and β€˜>’, matches itself.


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


       Matches any single character.


       [char-class]
               Matches  any single character in char-class.  To include a  β€˜]’
               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 β€˜-’, e.g.,  β€˜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 β€˜-’ 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  β€˜^’ 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  β€˜$’  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 β€˜\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
               β€˜\(a.c\)\1’  matches  the  string  β€˜abcabc’,  but not β€˜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  β€˜*’ operator sometimes yields
               unexpected results.  For example, the regular  expression  β€˜b*’
               matches  the  beginning of the string β€˜abbb’, as opposed to the
               substring β€˜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
               subexpression, then it is interpreted literally (i.e., the reg-
               ular expression β€˜\{2\}’ matches the string β€˜{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.

       \β€˜
       \’      Unconditionally  matches the beginning (\β€˜) or ending (\’) of a
               line.

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

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


       \b      Matches the beginning or ending (null string) of a word.   Thus
               the   regular   expression   β€˜\bhello\b’   is   equivalent   to
               β€˜\<hello\>’.  However, β€˜\b\b’ is  a  valid  regular  expression
               whereas β€˜\<\>’ 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 additonal
       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 β€˜€™ (print), β€˜€™ (list)
       , or β€˜€™ (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 β€˜!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 β€˜€™ 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 β€˜€™, β€˜€™, β€˜€™,
               and  β€˜€™.   A  newline alone in command-list is equivalent to a
               β€˜€™ 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  β€˜€™ 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 β€˜€™ com-
               mand.  A newline alone acts as a null command list.   A  single
               β€˜&’ 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 β€˜!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 β€˜€™ (global) suffix is given,
               then every match to be replaced.  The β€˜€™ suffix, where n is  a
               postive  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 β€˜€™ command below).  If one or two
               of the last delimiters is omitted, then the last line  affected
               is printed as though the print suffix β€˜€™ were specified.


               An  unescaped  β€˜&’  in replacement is replaced by the currently
               matched text.  The character sequence β€˜\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  β€˜%’,  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 β€˜€™ command
               accepts a count suffix β€˜€™, or any combination of  the  charac-
               ters  β€˜€™,  β€˜€™, and β€˜€™.  If a count suffix β€˜€™ is given, then
               only the nth match is replaced.  The β€˜€™ suffix causes the reg-
               ular  expression  of  the last search to be used instead of the
               that of the last substitution.   The  β€˜€™  suffix  toggles  the
               global suffix of the last substitution.  The β€˜€™ 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 β€˜€™,  β€˜€™,
               β€˜€™, and β€˜€™.  are treated as a single command by undo.  β€˜€™ 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 β€˜€™ com-
               mand.

       (1,$)V/re/
               Interactively edits the addressed lines not matching a  regular
               expression re.  This is similar to the β€˜€™ 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 β€˜€™
               command.

       (1,$)w !command
               Writes the addressed lines to the standard input of β€˜!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  β€˜€™ 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 β€˜€™, β€˜€™, β€˜€™, β€˜€™, or β€˜€™
               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 β€˜!’, then it is replaced by text of the previous β€˜!command’.
               ed does not process command for backslash  (\)  escapes.   How-
               ever,  an  unescaped  β€˜€™  is replaced by the default filename.
               When the shell returns from execution, a β€˜!’  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

       /tmp/ed.*           Buffer file
       ed.hup              The  file to which ed attempts to write the  buffer
                           if the terminal 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 β€˜?’ and returns to  command
       mode.   An  explanation  of  the last error can be printed with the β€˜€™
       (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.



                               10 November 1994                          ED(1)

Man(1) output converted with man2html