This question already has answers here:
Difference between single and double quotes in Bash
(7 answers)
Closed 4 years ago.
I have an environment variable LIB_HOME=/etc/temp
In one of the config files, i'm trying to replace entire line using sed command as follows
sed -i '/lib.home=/c\lib.home=$LIB_HOME' myconfig.properties
Actual Output : lib.home=blablabla ===> lib.home=$LIB_HOME
Expected Output : lib.home=blablabla ===> lib.home=/etc/temp
Please help
Have you tried using double quotes?
sed -i '/lib.home=/c\lib.home=‘“$LIB_HOME”' myconfig.properties
Related
This question already has answers here:
Difference between single and double quotes in Bash
(7 answers)
Closed 6 months ago.
How to replace a string in a file by bash variable, please
I tried
i="1"
sed -i 's/%q/0$i/g' file
sed -i 's/%q/0"$i"/g' file
There is 0$i or 0"$i" in the file instead of 01. Thank you
Change your script as follow:
i="1"
sed -i "s/%q/0$i/g" file
sed -i "s/%q/0\"$i\"/g" file
and remember: the shell variables substitution does not happen inside single quotes. ;)
This question already has answers here:
Difference between single and double quotes in Bash
(7 answers)
Closed 4 years ago.
I am having a problem while using the bash shell. Here is my linux command code:
for i in `cat linshi`;do sed -i '/$i/d' a.txt;done
The content of linshi is:
aa
bb
The content of a.txt is:
aa:wwersdf12314231234
bb:weorpius2345234523
cc:ertoiu230498234098
dd:234092834asdfkdfkg
I want to delete the first and the second row of a.txt.
But unlucky, I found '/$i/d' is not correct. And I have tried '/\$i/d' and '/"\"$id/', but they are fail again. Who can help me?
Variables aren't expanded inside single quotes, only double quotes.
for i in `cat linshi`; do sed -i "/$i/d" a.txt; done
That said, you could do the same thing with:
grep -vf linshi a.txt
Instead of using single quotes use double quotes. '' doesn't undergo any variable expansion however double quotes do.
This will work:
for i in $(cat linshi);do sed -i "/$i/d" a.txt;done
This question already has answers here:
How to replace a value with the output of a command in a text file?
(2 answers)
Closed 5 years ago.
my sed input is as follows:
sed 's/ListenAddress=.*/ListenAddress= $hostname/' nodemanager.properties
I am trying to run this against a Linux server and replace ListenAddress={current_value} with ListenAddress={hostname_of_server}
I need to know how to run the hostname command and have that output be reflected at the end of ListenAddress=
Thanks
If you wish your bash variables to reflect inside the sed script use, double quotes. The same is valid for command substitution. So you should be doing
sed "s/ListenAddress=.*/ListenAddress= $(hostname)/" nodemanager.properties
Since thevariable expansion takes place, you need to be careful about certain situations where $ appear as a sed attribute. For example if you're applying the above command only to the last line of the file, then do
sed "\$s/ListenAddress=.*/ListenAddress= $(hostname)/" nodemanager.properties
Note the $ before s command is escaped meaning that it is literal $ supplied to the script.
This question already has answers here:
Replace a string in shell script using a variable
(12 answers)
Closed 8 years ago.
I have an xml file with line below
<config-root>/temp</config-root>
Using 'sed' is bash shell script I want to replace the line,
the 'sed' script is below
sed -i 's/<config-root>\(.*\)<\/config-root>/<config-root>\"${dirPath}"<\/config-root>/' Plan.xml
The 'sed' is resulting in
<config-root>"${dirPath}"</config-root>
I am expecting the line to be replaced as /opt/shared
Can anyone let me know what is wrong in my script? Basically I want to use variable in ‘sed’
Thanks in advance,
Babu
You can use bash to place the variable in the sed script: End the sed script using the single quote ', place the variable in double quotes " and continue the sed program with another single quote ':
sed 's~<config-root>[^<]*</config-root>~<config-root>'"$variable"'</config-root>~' Plan.xml
I would encourage you to use delimiter different from / because the / is part of the pattern (and of the variable) and would need to get escaped otherwise. I used ~ as the delimiter.
This question already has answers here:
sed substitution with Bash variables
(6 answers)
Closed 7 years ago.
How can I do this?
sed -i 's/wiki_host/$host_name/g' /root/bin/sync
It will replace wiki_host with the text $host_name.
But I want to replace it with the content of the variable..
I tried it with
sed -i 's/wiki_host/${host_name}/g' /root/bin/sync
It doesn't work either.
You need to use double quotes:
$ sed -i "s/wiki_host/${host_name}/g" /root/bin/sync
Your single quotes prevent the shell variable from being replaced with its contents.