Benutzer:Andreas Plank/Sed: Unterschied zwischen den Versionen

Version vom 14. September 2011, 08:51 Uhr

Text snippets for the sed running under Linux.

#### file options
# -e execute
# -f file: script file
# -i insert into file: edit file in place
# -l 40 specify the desired line-wrap length for the “l” command
# -n nothing i.e. quiet
# -r extended regular expressions
# -s separate: consider files as separate
# -u unbuffered

#### actions 
# a → append action (after)
#     $a append after last line
# c → change: You can replace the current line with the ‘c’ action
# d → delete action 
# i → insert action (before)
#     1i insert before 1st line
# n → ?read the next line
# p → print action
# q → quit immediately without further processing

#### ACTIONS 
# D → delete up to the first embedded newline in the pattern space
# N → ?append the next line


#### addresses for instance with p → print
  '1,10p' # line 1 to 10
  '/beginRE/,/endRE/p' # reg. expr: beginRE to endRE
  '10~2p' # at line 10 then each 2nd line
  '$='    # last line “$” and provide “=” the line
#### examples
# sorted lines → delete duplicate lines
  sed '$!N; /^\(.*\)\n\1$/!P; D' temp2.txt > temp3.txt
# delete: 
  sed -e '1,10d' # line 1-10
  sed -e '11,$d' # line 11 to end of file
  sed -e '10~2d' # delete every 2nd line starting from 10
# extract:
  sed -n -e '1,10p'
# quit 
  sed -e '10q' # quit 
# commands on multiple lines or with -e again:
  sed -e '1,4d  
    6,9d'
  sed -e '1,4d' -e '6,9d'
# delete lines with debug + print lines with foo
  sed -n -e '/debug/d' -e '/foo/p'

# pipes
  gcc sourcefile.c 2>&1 | sed -n -e '/warning:/,/error:/p'

Sed help

### Command line syntax ###############
#   file ↘
#    sed -f sed_replacements.sed old_file.txt > new_file.txt
# insert ↘    ↙ file
#    sed -i -f sed_replacements.sed overwritten.txt

### Regular expressions ###############
# note the different (default) regexpr !!!
# summarised: + is + ? is ? ( is ( { is { | is | → all no expressions!
#   (..) → \(\)    reference 
#   ?    → \?      0 or 1
#   .+   → .\+     1 or many
#   .*   → .*      0 or many
#   [..] → [..]    character definition range
#   {..} → \{..\}
#   | → \| means “or”

### Seachr and replace ################
#  ↙ search          ↙ global scope
# s/search/replace/g

### Search and replace (address) ######
#   /address/s/search/replace/g
# NOT-matched or everything except “address”
#   /address/!s/search/replace/g
# address can be: 1,$ (1st line to the end) or a seach pattern

### multiline search with “address” ###
#               “address”
#┌─────────────────┴─────────────────────┐
#   first line   append \n  second line
#┌───────┴────────┐ ↓  ┌────────┴────────┐ 
/first line pattern/N;/second line pattern/{
  # do something with the found pattern
  #     search                replace       global scope
  #       ↓                      ↓          ↓
  s@first line\nsecond line@replace pattern@g
}

Ersetzungen mit MediaWiki-XML-Export

Siehe Sed help.

 ######### MediaWiki Export ##########
 #  don't replace!!
 #    → &nbps;
 #  &lt;br /&gt; → <br/>
 #####################################
 
 # set username
 # syntax explained
 #       first line           and append \n and second line
 #┌───────────┴───────────────────┐ ↓  ┌───────────┴──────────────┐ 
 /\(<username>\).\+\(<\/username>\)/N;/\(.\+<id>\)[0-9]\+\(<\/id>\)/{
   # do something with the found pattern
   # replace user name and user ID now with "\n"
   s@\(<username>\).\+\(</username>\n.\+<id>\)[0-9]\+\(</id>\)@\1Ihr Name\2123\3@g
 }
 
 # comment
 s@\(<comment>\).\+\(</comment>\)@\1alle Kommas in Semikolon (Stichworte, Ort)\2@g
 
 # delete revision
 /\(<revision>\)/N;/\( \+<id>\)[0-9]\+\(<\/id>\)/{
 s@\(<revision>\n \+<id>\)[0-9]\+\(<\/id>\)@\1\2@g
 }
 
 # timestamp  (-2 hours)
 s@\(<timestamp>\).\+\(</timestamp>\)@\12011-09-08T10:12:11Z\2@g
 
 # do your replacements here
 /^|\(Stichworte\|Ort\) *=.\+$/{
   s@,@;@g
 }