How to use sed to remove certain text base on regular expression

05
2013-09
  • forestclown

    I got a text file with contents like below

    2012/03/15 : "Password":"@#4JF9u92r","Name":"John"

    I wish to use sed to change the above to 

    2012/03/15 : "Password":"XXX","Name":"John"

    I have tried the following command 

    cat log.txt | sed 's/\("Password":\"\)\(.*\)\(\",\"Name\":\)/\1XXX/'

    But it gives me

    2012/03/15 : "Password":"XXX"John"

    What did I do wrong?

    Thanks!

    • Answers
  • bmk

    You should slightly change your sed command:

    sed 's/\("Password":\"\).*\(\",\"Name\":\)/\1XXX\2/'
  • Siva Charan

    Below regex is the base one, place necessary escape characters

    (\s"Password":")(.*?)(","Name":"(.*?)")

    Replace with \1XXX\3

    After placing proper escape characters, I think it should be something like this.

    cat log.txt | sed '\(s/\"Password\":\"\)\(.*?\)\(\",\"Name\":\"\(.*?\)\"\)/\1XXX\3/'
  • potong

    This might work for you:

    echo '2012/03/15 : "Password":"@#4JF9u92r","Name":"John"' |
sed 's/\("Password":"\)[^"]*/\1XXX/'
2012/03/15 : "Password":"XXX","Name":"John"

    • Related Question

    osx - How can I use sed to alter the results of find and pass the results to cp?
  • Michael Prescott

    In solaris, I'd like to copy all files found by the find command to a slightly different path. The following script basically executes cp for each file found by find. For example:

    cp ./content/english/activity1_compressed.swf ./content/spanish/activity1_compressed.swf
cp ./content/english/activity2_compressed.swf ./content/spanish/activity2_compressed.swf
...

#!/bin/bash

# Read all file names into an array
FilesArray=($(find "." -name "*_compressed.swf"))

# Get length of an array
FilesIndex=${#FilesArray[@]}

# Copy each file from english to spanish folder
# Ex: cp ./english/activity_compressed.swf ./spanish/activity_compressed.swf
for (( i=0; i<${FilesIndex}; i++ ));
do
    source="${FilesArray[$i]}"

    # Replace "english" with "spanish" in path  
    destination="$(echo "${source}" | sed 's/english/spanish/')"

    cp "${source}" "${destination}"
done

exit 0;

    It seems like a bit much and I wonder how to use sed in-line with the find and cp commands to achieve the same thing. I would have hoped for something like the following, but apparently parentheses aren't acceptable method of changing order of operation:

    find . -name *_compressed -exec cp {} (echo '{}' | sed 's/english/spanish/')

    • Related Answers
  • John T

    There are easier ways, but for portability sake we can use a bit of forking and backticks:

    find . -name *_compressed -exec sh -c 'cp {} `echo {} | sed 's/english/spanish/'`' \;
  • Tom Wijsman

    I'd use the backtick: you'll find more upon it here (backtick is at chapter 3.4.5).

    Basically when you enclose a command between backticks the command itself will be substituted in his output.