==================== 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 "\n" 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 | |
'---------------------'-----------------------------------------------'
Thursday, 21 March 2013
Sed Stream Editor Cheat Sheet
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