I have scenario where i want to replace the digit or string after equal to = to null [ blank ]
Without creating new file need to replace in the same file
Data in file :
name=vilas
age=21
code=1345
Need to replace the digit after code=1345 to code=
I have tried this but stuck
sed -i 's/^code=$/code=/1g' file.txt
Note : The value after code= is going to be dynamic need to use regex pattern match which i am not good with
var1=456
$ sed -Ei "s/(code=).*/\1$var1/" file
name=vilas
age=21
code=456
Based on your question:
On MacOS and FreeBSD
sed -i '' -E 's/^code=[[:digit:]]+$/code=/g' test1.txt
On CentOS and Debian
sed -i -E 's/^code=[[:digit:]]+$/code=/g' test1.txt
You can update the character class to fit your needs.
where
-i Edit files in-place
-E Interpret regular expressions as extended (modern) regular expressions rather than basic regular expressions (BRE's).
s The substitute command
g Apply the replacement to all matches to the regexp, not just the first.
GNU docs: https://www.gnu.org/software/sed/manual/html_node/Character-Classes-and-Bracket-Expressions.html
SED docs: https://www.gnu.org/software/sed/manual/sed.html
Related
I have a file:
dynamicclaspath.cfg
VENDOR_JAR=/clear-as-1-d/apps/sterling/jar/struts/2_5_18/1_0_0/log4j-core-2.10.0.jar
VENDOR_JAR=/clear-as-1-d/apps/sterling/jar/log4j/2_17_1/log4j-core-2.10.0.jar
I want to replace any occurrence of log4j-core* with log4j-core-2.17.1.jar
I tried this but I know I'm missing a regex:
sed -i '/^log4j-core/ s/[-]* /log4j-core-2.17.1.jar/'
With your shown samples please try following sed program. Using -E option with sed to enable ERE(extended regular expressions) with it. In main program using substitute option to perform substitution. Using sed's capability to use regex and store matched values into temp buffer(capturing groups). Matching till last occurrence of / and then matching log4j-core till jar at last of value. While substituting it with 1st capturing group value(till last occurrence of /) followed by new value of log4j as per OP's requirement.
sed -E 's/(^.*\/)log4j-core-.*\.jar$/\1log4j-core-2.17.1.jar/' Input_file
Using sed
$ sed -E 's/(log4j-core-)[0-9.]+/\12.17.1./' input_file
VENDOR_JAR=/clear-as-1-d/apps/sterling/jar/struts/2_5_18/1_0_0/log4j-core-2.17.1.jar
VENDOR_JAR=/clear-as-1-d/apps/sterling/jar/log4j/2_17_1/log4j-core-2.17.1.jar
It depends on possible other contents in your input file how specific the search pattern must be.
sed 's/log4j-core-.*\.jar/log4j-core-2.17.1.jar/' inputfile
or
sed 's/log4j-core-[0-9.]*\.jar/log4j-core-2.17.1.jar/' inputfile
or (if log4j-core*.jar is always the last part of the line)
sed 's/log4j-core.*/log4j-core-2.17.1.jar/' inputfile
sed -i s'#2.10.0.jar$#2.17.1.jar#'g file
That seems to work.
I have a configuration file (gpsd.default) containing data with the following format:
# If you must specify a non-NMEA driver, uncomment and modify the next line
GPSD_SOCKET="/var/run/gpsd.sock"
GPSD_OPTIONS=""
GPS_DEVICES=""
I am making a change on the file with sed:
sed -i 's/^GPS_DEVICES="".*/GPS_DEVICES="dev/ttyUSB1"/' /etc/default/gpsd.default
or
sed -i '4s/^.*/GPS_DEVICES="dev/ttyUSB1"/' /etc/default/gpsd.default
The above sed command returns error:
sed: bad option in substitution expression
Because the new line contains "/" in its expression.
How to update my sed command to make it work?
This is because you are using a regex containing /, which is the same character sed uses as delimiter.
Just change the sed delimiter to another one, for example ~:
sed -i 's~^GPS_DEVICES="".*~GPS_DEVICES="dev/ttyUSB1"~' /etc/default/gpsd.default
By the way, since you are changing files in /etc, you may want to use -i.bak, so that the original file gets backed up. It is a good practice to prevent loss of important information.
You should update your sed command to this.
sed -i 's/^GPS_DEVICES=\"\".*/GPS_DEVICES=\"dev\/ttyUSB1\"/' /etc/default/gpsd.default
I am trying to change a line with a pattern in a textual file using Linux bash.
I tried the sed command:
sed -i 's/old/new/' < file.txt
The issue with this command line I have to specify the exact "old" word. I want to change thousands of files where the old word has a pattern like this: old1(, old2(,old3(,....old10000(
I would like to change the oldxxx( in all files to old1(
Any ideas how to do this?
You can use something like:
sed -i 's/old[0-9]\{1,\}(/old1(/' file.txt
This matches "old" followed by one or more digits and a "(" and replaces it with "old1(".
If your version of sed supports extended regular expressions, you can use:
sed -r -i 's/old[0-9]+\(/old1(/' file.txt
instead, which does the same thing. On some versions of sed, the -E switch is used instead of -r.
If you have more than one instance of the pattern "oldXX(" on the same line, you may also want to the g modifier (s/.../.../g) to do a global replacement.
I have a file having data in the following form
<A/Here> <A/There>
<B/SomeMoreDate> <C/SomeOtherDate>
Now I want to delete all the A,B,C from the file in an efficient way. I know I can use sed for one pattern
sed -i 's/A//g' /path/to/filename.
But how do I specify such that sed to contain an or to deletes all the patterns?
The expected output is:
<Here> <There>
<SomeMoreDate> <SomeOtherDate>
You can use sed -i 's/[ABC]//g' /path/to/filename. [ABC] will match either A or B or C. You may find this reference useful.
If you're using GNU sed, you can say:
sed -r 's#(A|B|C)/##g' filename
The following should work otherwise:
sed 's#A/##g;s#B/##g;s#C/##g' filename
Ivaylo Strandjev's answer is correct in that it solves the problem when wanting to match single characters. There is a way though to have or when matching longer strings.
s/\(\(stringA\)\|\(stringB\)\|\(stringC\)\)something/something else/
You can try with somehting like:
echo stringBsomething | sed -e 's/\(stringA\|stringB\|stringC\)something/something else/'
It is sad that sed requires all these backslashes. Some if this is avoided if you use -r.
sed "s/<[ABC]\//</g" /path/to/filename
because it is a special case of 1 char in length changing in the pattern. This is not a real OR
you can use this workaround on limited to POSIX sed
Sample for test purpose
echo "<Pat1/ is pattern 2> <pat2/ is pattern 2>
<pAt3/ is pattern 3>
<pat4/ is pattern 4> but not avalaible for Pat1/ nor <pat2
" | \
The sed part
sed 's/²/²o/g
t myor
:myor
s/<Pat1\//²p/g;t treat
s/<pat2\//²p/g;t treat
s/<pAt3\//²p/g;t treat
b continu
: treat
s/²p/</g
t myor
: continu
s/²o/²/g
'
This use a temporary char as generic pattern "²" and a series of s/ followed by a test branch as OR functionality
I'm trying to write a shell script that does a search and replace inside a configuration file upon start-up.
The string we're trying to replace is:
include /etc/nginx/https.include;
and we want to replace it with a commented version:
#include /etc/nginx/https.include;
The file that contains the string that we want to replace is:
/etc/nginx/app-servers.include
I'm not a Linux guru and can't seem to find the command to do this.
perl -p -i -e 's%^(include /etc/nginx/https.include;)$%#$1%' /etc/nginx/ap-servers.include
If the line might not end in the ;, use instead:
perl -p -i -e 's%^(include /etc/nginx/https.include;.*)$%#$1%' /etc/nginx/ap-servers.include
If you want to preserve the original file, add a backup extension after -i:
perl -p -i.bak -e 's%^(include /etc/nginx/https.include;)$%#$1%' /etc/nginx/ap-servers.include
Now, explaining. The -p flag means replace in-place. All lines of the file will be fed to the expression, and the result will be used as replacement. The -i flag indicates the extension of the backup file. By using it without anything, you prevent generation of backups. The -e tells Perl to get the following parameter as an expression to be executed.
Now, the expression is s%something%other%. I use % instead of the more traditional / to avoid having to escape the slashes of the path. I use parenthesis in the expression and $1 in the substituted expression for safety -- if you change one, the other will follow. Thus, %#$1% is actually the second % of s, followed by the desired #, $1 indicating the pattern inside parenthesis, and the last % of s.
HTH. HAND.
sed -i 's/foo/bar/g' config.txt
This replaces all instances of foo (case insensitive) with bar in the file config.txt
Check out sed:
sed -i -r 's|^(include /etc/nginx/https.include;)$|#\1|' /etc/nginx/app-servers.include
-i means do the substitution in-place and -r means to use extended regular expressions.
cd pathname
for y in `ls *`;
do sed "s/ABCD/DCBA/g" $y > temp; mv temp $y;
done
This script shold replace string ABCD to DCBA in all the files in pathname