ED(I)                        1/15/73                        ED(I)


     ed - text editor


     ed [ - ] [ name ]


     Ed is the standard text editor.

     If a name argument is given, ed simulates an e command  (see

     below)  on  the named file; that is to say, the file is read

     into ed's buffer so that it can be edited.  The  optional  -

     suppresses  the  printing of character counts by e, r, and w


     Ed operates on a copy of any file  it  is  editing;  changes

     made  in  the  copy  have  no  effect  on the file until a w

     (write) command is given.  The copy of the text being edited

     resides  in  a  temporary  file called the buffer.  There is

     only one buffer.

     Commands to ed have a simple and regular structure: zero  or

     more  addresses  followed  by  a  single  character command,

     possibly followed  by  parameters  to  the  command.   These

     addresses  specify  one  or more lines in the buffer.  Every

     command which requires addresses has default  addresses,  so

     that the addresses can often be omitted.

     In general, only one command may appear on a line.   Certain

     commands  allow  the  input of text.  This text is placed in

     the appropriate place in the buffer.  While ed is  accepting

     text,  it  is  said  to  be in input mode.  In this mode, no

     commands are recognized;  all  input  is  merely  collected.

     Input  mode  is  left  by  typing  a period `.' alone at the

     beginning of a line.

     Ed supports a limited form of regular  expression  notation.

     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.  The regular expressions

     allowed by ed are constructed as follows:

     1.  An ordinary character (not one of those discussed below)

        is a regular expression and matches that character.

     2.  A  circumflex  `^'  at  the  beginning  of   a   regular

        expression matches the empty string at the beginning of a


     3.  A currency symbol `$' at the end of a regular expression

        matches the null character at the end of a line.

     4.  A period `.' matches any  character  except  a  new-line


     5.  A regular expression followed by an asterisk `*' matches

        any  number  of  adjacent occurrences (including zero) of

        the regular expression it follows.

     6.  A string of characters enclosed in square brackets `[ ]'

        matches  any  character in the string but no others.  If,

        however,  the  first  character  of  the  string   is   a

        circumflex   `^'   the  regular  expression  matches  any

        character except  new-line  and  the  characters  in  the


     7.  The concatenation of regular expressions  is  a  regular

        expression which matches the concatenation of the strings

        matched by the components of the regular expression.

     8.  A regular expression enclosed between the sequences `\('

        and  `\)'is  identical  to  the unadorned expression; the

        construction has  side  effects  discussed  under  the  s


     9.  The null regular expression standing alone is equivalent

        to the last regular expression encountered.

     Regular expressions are used in addresses to  specify  lines

     and  in  one command (see s below) to specify a portion of a

     line which is to be replaced.  If it is desired to  use  one

     of  the  regular  expression  metacharacters  as an ordinary

     character, that character may be preceded by `\'.  This also

     applies  to  the  character  bounding the regular expression

     (often `/') and to `\' itself.

     To understand addressing in ed it is necessary to know  that

     at  any  time  there is a current line.  Generally speaking,

     the current line is the last line  affected  by  a  command;

     however,  the  exact effect on the current line is discussed

     under  the  description  of  the  command.   Addresses   are

     constructed as follows.

        1.  The character `.' addresses the current line.

        2.  The character `$' addresses  the  last  line  of  the


        3.  A decimal number n addresses the  n-th  line  of  the


        4.  `'x' addresses the line marked  with  the  mark  name

           character x, which must be a lower-case letter.  Lines

           are marked with the k command described below.

        5.  A  regular  expression  enclosed   in   slashes   `/'

           addresses the first line found by searching toward the

           end of the buffer  and  stopping  at  the  first  line

           containing  a  string matching the regular expression.

           If necessary the search wraps around to the  beginning

           of the buffer.

        6.  A  regular  expression  enclosed   in   queries   `?'

           addresses the first line found by searching toward the

           beginning of the buffer and stopping at the first line

           containing  a  string matching the regular expression.

           If necessary the search wraps around to the end of the


        7.  An address followed by a plus sign  `+'  or  a  minus

           sign  `-'  followed by a decimal number specifies that

           address plus (resp. minus)  the  indicated  number  of

           lines.  The plus sign may be omitted.

        8.  If an address begins with `+' or `-' the addition  or

           subtraction is taken with respect to the current line;

           e.g. `-5' is understood to mean `.-5'.

        9.  If an address ends with `+' or `-', then 1  is  added

           (resp. subtracted).  As a consequence of this rule and

           rule 8, the address `-' refers to the line before  the

           current   line.    Moreover,   trailing  `+'  and  `-'

           characters have cumulative effect, so `--'  refers  to

           the current line less 2.

        10. To maintain compatibility with earlier version of the

           editor,  the  character  `^'  in addresses is entirely

           equivalent to `-'.

     Commands may require zero, one, or two addresses.   Commands

     which require no addresses regard the presence of an address

     as an error.  Commands which accept  one  or  two  addresses

     assume  default  addresses  when insufficient are given.  If

     more addresses are given than such a command  requires,  the

     last one or two (depending on what is accepted) are used.

     Addresses are separated from each other typically by a comma

     `,'.   They  may  also  be separated by a semicolon `;'.  In

     this case the current  line  `.'  is  set  to  the  previous

     address  before  the  next  address  is  interpreted.   This

     feature can be used  to  determine  the  starting  line  for

     forward  and  backward  searches  (`/',  `?').   The  second

     address of any two-address sequence  must  correspond  to  a

     line following the line corresponding to the first address.

     In the following list of ed commands, the default  addresses

     are  shown  in parentheses.  The parentheses are not part of

     the address, but are used to show that the  given  addresses

     are the default.

     As mentioned, it is generally  illegal  for  more  than  one

     command  to  appear  on a line.  However, any command may be

     suffixed by `p' or by `l', in which case the current line is

     either  printed  or listed respectively in the way discussed


     ( . )a



           The append command reads the given text and appends it

          after the addressed line.  `.' is left on the last line

          input, if there were any, otherwise  at  the  addressed

          line.   Address  `0' is legal for this command; text is

          placed at the beginning of the buffer.

     ( . , . )c



           The change command deletes the addressed  lines,  then

          accepts  input text which replaces these lines.  `.' is

          left at the last line input; if there were none, it  is

          left at the first line not deleted.

     ( . , . ) d

          The delete command deletes the addressed lines from the

          buffer.   The  line  originally  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.

     e filename

          The edit command causes  the  entire  contents  of  the

          buffer  to  be  deleted,  and then the named file to be

          read in.  `.' is set to the last line  of  the  buffer.

          The  number of characters read is typed.  `filename' is

          remembered for possible use as a default file name in a

          subsequent r or w command.

     f filename

          The filename command prints  the  currently  remembered

          file  name.   If  `filename'  is  given,  the currently

          remembered file name is changed to `filename'.

     (1,$)g/regular expression/command list

          In the global command, the first step is to mark  every

          line  which matches the given regular expression.  Then

          for every such line, the given command list is executed

          with  `.' initially set to that line.  A single command

          or the first of multiple commands appears on  the  same

          line  with  the  global command.  All lines of a multi-

          line list except the last line must be ended with  `\'.

          A,   i,   and  c  commands  and  associated  input  are

          permitted;  the  `.'  terminating  input  mode  may  be

          omitted  if it would be on the last line of the command

          list.   The  (global)  commands,  g,  and  v,  are  not

          permitted in the command list.

     ( . )i



          This  command  inserts  the  given  text   before   the

          addressed line.  `.' is left at the last line input; if

          there were none, at the addressed line.   This  command

          differs from the a command only in the placement of the


     ( . )kx

          The mark command marks the addressed line with name  x,

          which  must  be  a lower-case letter.  The address form

          `'x' then addresses this line.

     ( . , . )l

          The list command  prints  the  addressed  lines  in  an

          unambiguous  way: non-graphic characters are printed in

          octal, and long lines are folded.   An  l  command  may

          follow any other on the same line.

     ( . , . )ma

          The move command repositions the addressed lines  after

          the  line  addressed by a.  The last of the moved lines

          becomes the current line.

     ( . , . )p

          The print command prints the addressed lines.  `.'   is

          left  at  the  last line printed.  The p command may be

          placed on the same line after any command.


          The quit command causes ed to exit.  No automatic write

          of a file is done.

     ($)r filename

          The read command reads in  the  given  file  after  the

          addressed   line.   If  no  file  name  is  given,  the

          remembered file name, if any, is  used  (see  e  and  f

          commands).   The  remembered  file  name is not changed

          unless  `filename'  is  the  very   first   file   name

          mentioned.   Address  `0' is legal for r and causes the

          file to be read at the beginning of the buffer.  If the

          read  is  successful,  the number of characters read is

          typed.  `.' is left at the last line read in  from  the


     ( . , . )s/regular expression/replacement/         or,

     ( . , . )s/regular expression/replacement/g

          The substitute command searches each addressed line for

          an  occurrence of the specified regular expression.  On

          each line in  which  a  match  is  found,  all  matched

          strings  are  replaced by the replacement specified, if

          the global replacement indicator `g' appears after  the

          command.  If the global indicator does not appear, only

          the first occurrence of the matched string is replaced.

          It  is  an  error  for  the substitution to fail on all

          addressed lines.  Any character  other  than  space  or

          new-line  may  be  used  instead  of `/' to delimit the

          regular expression and the replacement.  `.' is left at

          the last line substituted.

          An  ampersand  `&'  appearing  in  the  replacement  is

          replaced by the string matching the regular expression.

          The special meaning of  `&'  in  this  context  may  be

          suppressed  by  preceding it by `\'.  As a more general

          feature, the characters `\n', where n is a  digit,  are

          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.

          Lines may be split by substituting new-line  characters

          into them.  The new-line in the replacement string must

          be escaped by preceding it by `\'.

     ( . , . ) t a

          This command acts just like the m command, except  that

          a copy of the addressed lines is placed after address a

          (which may be 0).  `.' is left on the last line of  the


     (1,$)v/regular expression/command list

          This command is the same as the global  command  except

          that  the  command  list is executed with `.' initially

          set to every line except  those  matching  the  regular


     (1,$)w filename

          The write command writes the addressed lines  onto  the

          given  file.  If the file does not exist, it is created

          mode 666 (readable and  writeable  by  everyone).   The

          remembered  file  name is not changed unless `filename'

          is the very first file name mentioned.  If no file name

          is  given,  the  remembered  file name, if any, is used

          (see e and f commands).   `.'  is  unchanged.   If  the

          command is successful, the number of characters written

          is typed.


          The line number of the addressed line is typed.  `.' is

          unchanged by this command.

     !UNIX command

          The remainder of the line after the `!' is sent to UNIX

          to be interpreted as a command.  `.' is unchanged.

     ( .+1 )<newline>

          An address alone on a line causes the addressed line to

          be  printed.   A  blank  line  alone  is  equivalent to

          `.+1p'; it is useful for stepping through text.

     If an interrupt signal (ASCII DEL) is sent, ed prints a  `?'

     and returns to its command level.

     Some  size  limitations:  512  characters  per   line,   256

     characters  per  global command list, 64 characters per file

     name, and 128K characters in the temporary file.  The  limit

     on  the  number of lines depends on the amount of core: each

     line takes 1 word.


     /tmp/#, temporary; `#' is the process number (in octal).


     `?'  for  errors  in  commands;  `TMP'  for  temporary  file



     A Tutorial  Introduction  to  the  ED  Text  Editor  (B.  W.



     The s command causes all marks to be lost on lines changed.