Sed Cheat Sheet

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|                                                                     |
|                            UNIX Stream Editor                       |
|                             Sed Cheat Sheet                         |
|                                                                     |
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| Created by Peter Krumins (peter@catonmat.net, @pkrumins on twitter) |
| www.catonmat.net -- good coders code, great coders reuse            |
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 ==================== How Commands Affect Streams ====================

   .---------.-----------.-----------------------------------------.
   |         |           |           Modifications to:             |
   |         |  Address  '---------.---------.---------.-----------'
   | Command | or Range  | Input   | Output  | Pattern |   Hold    |
   |         |           | Stream  | Stream  | Space   |   Buffer  |
   '---------+-----------+---------+---------+---------+-----------'
   |    =    |     -     |    -    |    +    |    -    |     -     |
   |    a    |     1     |    -    |    +    |    -    |     -     |
   |    b    |     2     |    -    |    -    |    -    |     -     |
   |    c    |     2     |    -    |    +    |    -    |     -     |
   |    d    |     2     |    +    |    -    |    +    |     -     |
   |    D    |     2     |    +    |    -    |    +    |     -     |
   |    g    |     2     |    -    |    -    |    +    |     -     |
   |    G    |     2     |    -    |    -    |    +    |     -     |
   |    h    |     2     |    -    |    -    |    -    |     +     |
   |    H    |     2     |    -    |    -    |    -    |     +     |
   |    i    |     1     |    -    |    +    |    -    |     -     |
   |    l    |     1     |    -    |    +    |    -    |     -     |
   |    n    |     2     |    +    |    *    |    -    |     -     |
   |    N    |     2     |    +    |    -    |    +    |     -     |
   |    p    |     2     |    -    |    +    |    -    |     -     |
   |    P    |     2     |    -    |    +    |    -    |     -     |
   |    q    |     1     |    -    |    -    |    -    |     -     |
   |    r    |     1     |    -    |    +    |    -    |     -     |
   |    s    |     2     |    -    |    -    |    +    |     -     |
   |    t    |     2     |    -    |    -    |    -    |     -     |
   |    w    |     2     |    -    |    +    |    -    |     -     |
   |    x    |     2     |    -    |    -    |    +    |     +     |
   |    y    |     2     |    -    |    -    |    +    |     -     |
   '---------'-----------'---------'---------'---------'-----------'

    Modifications to:

    1    Command takes single address or pattern.
    2    Command takes pair of addresses.
    -    Command does not modify the buffer.
    +    Command modifies the buffer.
    *    The ``n'' command may or may not generate output depending
         on the ``-n'' command option.


 ========================== Command Summary ==========================

.----------------.----------------------------------------------------.
|                |                                                    |
| Command        | Description                                        |
|                |                                                    |
'----------------+----------------------------------------------------'
| #              | Adds a comment.                                    |
'----------------+----------------------------------------------------'
| =              | The "=" command prints the current line number to  |
|                | standard output.                                   |
'----------------+----------------------------------------------------'
| a             | The "a" command appends text after the             |
| text           | range or pattern.                                  |
'----------------+----------------------------------------------------'
| b label        | The "b" command branches to the label. You can     |
|                | specify a label with a text string followed by a   |
|                | colon. If no label is there, branch to the end of  |
|                | the script.                                        |
'----------------+----------------------------------------------------'
| c             | The "c" command changes the current line with      |
| text           | text.                                              |
'----------------+----------------------------------------------------'
| d              | The "d" command deletes the current pattern space, |
|                | reads in the next line, puts the new line into the |
|                | pattern space, and aborts the current command, and |
|                | starts execution at the first sed command.         |
'----------------+----------------------------------------------------'
| D              | The "D" command deletes the first portion of the   |
|                | pattern space, up to the new line character,       |
|                | leaving the rest of the pattern alone.             |
'----------------+----------------------------------------------------'
| g              | Instead of exchanging (the "x" command) the hold   |
|                | space with the pattern space, you can copy the     |
|                | hold space to the pattern space with the "g"       |
|                | command.                                           |
'----------------+----------------------------------------------------'
| G              | If you want to append to the pattern space, use    |
|                | the "G" command.                                   |
'----------------+----------------------------------------------------'
| h              | The "h" command copies the pattern buffer into the |
|                | hold buffer.                                       |
'----------------+----------------------------------------------------'
| H              | The "H" command allows you to combine several      |
|                | lines in the hold buffer. It acts like the "N"     |
|                | command as lines are appended to the buffer, with  |
|                | a "
" between the lines. You can save several     |
|                | lines in the hold buffer, and print them only if a |
|                | particular pattern is found later.                 |
'----------------+----------------------------------------------------'
| i             | You can insert text before the pattern with        |
| text           | the "i" command.                                   |
'----------------+----------------------------------------------------'
| l              | The "l" command prints the current pattern space.  |
|                | It is therefore useful in debugging sed scripts.   |
|                | It also converts unprintable characters into       |
|                | printing characters by outputting the value in     |
|                | octal preceded by a "" character.                 |
'----------------+----------------------------------------------------'
| n              | The "n" command will print out the current pattern |
|                | space (unless the "-n" flag is used), empty the    |
|                | current pattern space, and read in the next        |
|                | line of input.                                     |
'----------------+----------------------------------------------------'
| N              | The "N" command does not print out the current     |
|                | pattern space and does not empty the pattern       |
|                | space. It reads in the next line, but appends a    |
|                | new line character along with the input line       |
|                | itself to the pattern space.                       |
'----------------+----------------------------------------------------'
| p              | Another useful command is the print command: "p".  |
|                | If sed wasn't started with an "-n" option, the "p" |
|                | command will duplicate the input. The "p" command  |
|                | prints the entire pattern space.                   |
'----------------+----------------------------------------------------'
| P              | The "P" command only prints the first part of the  |
|                | pattern space, up to the NEWLINE character.        |
'----------------+----------------------------------------------------'
| q              | There is one more simple command that can restrict |
|                | the changes to a set of lines. It is the "q"       |
|                | command: quit. This command is most useful when    |
|                | you wish to abort the editing after some condition |
|                | is reached.                                        |
'----------------+----------------------------------------------------'
| r filename     | The "r" command will append text from filename     |
|                | after the range or pattern.                        |
'----------------+----------------------------------------------------'
| s/regex/repl/  | The substitute command replaces all occurrences of |
|                | the regular expression (regex) with repl(acement)  |
'----------------+----------------------------------------------------'
| t label        | You can execute a branch if a pattern is found.    |
|                | You may want to execute a branch only if a         |
|                | substitution is made. The command "t label" will   |
|                | branch to the label if the last substitute command |
|                | modified the pattern space.                        |
'----------------+----------------------------------------------------'
| w filename     | With this command, you can specify a filename that |
|                | will receive the modified data.                    |
'----------------+----------------------------------------------------'
| x              | The "x" command exchanges the hold buffer and the  |
|                | pattern buffer.                                    |
'----------------+----------------------------------------------------'
| y/source/dest/ | Transliterate the characters in the pattern space, |
|                | which appear in source to the corresponding        |
|                | character in dest(ination).                        |
'----------------'----------------------------------------------------'


 ======================== Command Extensions =========================

.----------------.----------------------------------------------------.
|                |                                                    |
| Command        | Description                                        |
|                |                                                    |
'----------------+----------------------------------------------------'
| Q              | Immediately quit the sed script without processing |
|                | any more input. (zero or one address command)      |
'----------------+----------------------------------------------------'
| R filename     | Append a line read from filename. (zero or one     |
|                | address command).                                  |
'----------------+----------------------------------------------------'
| T label        | If no s/// has done a successful substitution      |
|                | since the last input line was read and since the   |
|                | last t or T command, then branch to label;         |
|                | if label is omitted, branch to end of script.      |
|                | (accepts address range).                           |
'----------------+----------------------------------------------------'
| W filename     | Write the first line of the current pattern space  |
|                | to filename. (accepts address range).              |
'----------------'----------------------------------------------------'


 ======================= Address Range Summary =======================

.----------------.----------------------------------------------------.
|                |                                                    |
| Format         | Description                                        |
|                |                                                    |
'----------------+----------------------------------------------------'
| number         | Match only the specified line number.              |
'----------------+----------------------------------------------------'
| first~step     | Match every step'th line starting with line first. |
'----------------+----------------------------------------------------'
| $              | Match the last line.                               |
'----------------+----------------------------------------------------'
| 0, addr2       | Start out in "matched first address" state,        |
|                | until addr2 is found.                              |
'----------------+----------------------------------------------------'
| /regex/        | Match lines matching the regular expression regex. |
'----------------+----------------------------------------------------'
| addr1,+N       | Will match addr1 and the N lines following addr1.  |
'----------------+----------------------------------------------------'
| cregexc       | Match lines matching the regular expression regex. |
|                | The c may be any character.                        |
'----------------+----------------------------------------------------'
| addr1,~N       | Will match addr1 and the lines following addr1     |
|                | until the next line whose input line number        |
|                | is a multiple of N.                                |
'----------------'----------------------------------------------------'


 ============== GNU Sed's Command Line Argument Summary ==============

.---------------------.-----------------------------------------------.
|                     |                                               |
| Argument            | Description                                   |
|                     |                                               |
'---------------------+-----------------------------------------------'
| -n                  |                                               |
| --quiet             | Suppress automatic printing of pattern space. |
| --silent            |                                               |
'---------------------+-----------------------------------------------'
| -e script           |                                               |  
| --expression=script | Add the script to the commands to be executed.|
|                     |                                               |
'---------------------+-----------------------------------------------'
| -f script-file      | Add the contents of script-file to the        |
| --file=script-file  | commands to be executed.                      |
'---------------------+-----------------------------------------------'
| -i[suffix]          | Sdit files in place (makes backup if          |
| --in-place[=suffix] | extension supplied).                          |
'---------------------+-----------------------------------------------'
| -l N                | Specify the desired line-wrap length for      |
| --line-length=N     | the `l' command.                              |
'---------------------+-----------------------------------------------'
| -r                  | Use extended regular expressions in the       |
| --regexp-extended   | script.                                       |
'---------------------+-----------------------------------------------'
| -s                  | Consider files as separate rather than as a   |
| --separate          | single continuous long stream.                |
'---------------------+-----------------------------------------------'
| -u                  | Load minimal amounts of data from the input   |
| --unbuffered        | files and flush the output buffers more often.|
'---------------------+-----------------------------------------------'
| --help              | Display this help and exit                    |
'---------------------+-----------------------------------------------'
| -V                  | Output version information and exit           |
| --version           |                                               |
'---------------------'-----------------------------------------------'

 =====================================================================

.---------------------------------------------------------------------.
| Created by Peter Krumins (peter@catonmat.net, @pkrumins on twitter) |
| www.catonmat.net -- good coders code, great coders reuse            |
'---------------------------------------------------------------------'