I'm trying to change a variable using sed, but its kinda different (for me, at least) so I couldn't find any answers online.
Here's basically what I'm trying to do;
sed -i '"/${_variable}"=0/c\"${_variable}=1"' ${_conf}
so in config file, there is a variable;
_variable=test
and the present file has this line;
${_variable}=0
so the variable changes to;
test=0
and I want to change this test=0 to test=1 but the text test is not a static content, it fetches its content from ${_variable}.
So how can I change this with sed?
Related
Working on a bash script. I'm reading a line from a properties file using grep and cut and have fetched some value in a variable role_portions something like this role_portions=role_1:10,role_2:25,role_3:75,role_4:50,role_5:75,role_6:25,role_7:50
Now, I get a few roles as csv input parameter in my bash script and I would want to change those roles values to 0.
For example, when I run modify_script.sh role_2,role_4,role_7, after reading the above value from the file, the script should provide as output role_1:10,role_2:0,role_3:75,role_4:0,role_5:75,role_6:25,role_7:0. Can someone help with this?
When the role names are without special characters (like & and /) you can use sed.
for role in role_2 role_4 role_7; do
role_portions=$(sed -r "s/(^|,)(${role}):[^,]*/\1\2:0/" <<< "${role_portions}")
done
When you are already using grep and cut you might be able to combine commands (maybe use awk).
I have the template file 12A-r.inp . I want to prepare files from this file whose name will be 16A-r.inp, 20A-r.inp, 24A-r.inp. And I want to change some parameter in those files according to their names. For example, I want to replace the string "12A" in all places in file 12A-r.inp, with 16A in 16A-r.inp, and 20A in 20A-r.inp. I have written the code below for this:
for ((i=12;i<=24;i=i+4))
do
cat 12A-r.inp >> $i\A-r.inp
done
for ((i=12;i<=24;i=i+4))
do
sed -i "s/12A/${i}/g" $i\A-r.inp
done
But the problem is 12A gets replaced by ${i}, not with strings like 16A, 20A etc.
Observations:
In for ((i=12;i<=24;i=i+4)) counts 12,16,20,24. There's no need
to start at 12, since the template is already correct. Worse,
when i=12, this code cat 12A-r.inp >> $i\A-r.inp appends a
copy of the template file onto itself, doubling it, which causes every ensuing
created file to be twice as long as the original template.
The \ in $i\A-r.inp is unnecessary, since A is not a special character.
The cat is unnecessary, sed without -i can do it all.
In sed, s/12A/${i}/g would replace the string "12A", with whatever number $i is, without the "A", unless the variable includes that letter.
The for loop uses a bashism to enumerate i... in this instance there's a simpler equivalent bashism, (see below).
Suggested revision:
for i in {16..24..4}A
do
sed "s/12A/${i}/g" 12A-r.inp > ${i}-r.inp
done
How it works:
$i is set to 16A,20A, and 24A.
sed repeatedly reads in the template, replaces 12A with $i,
prints everything to STDOUT...
which is redirected to the appropriately named file.
This question already has answers here:
Replace a string in shell script using a variable
(12 answers)
Closed 6 years ago.
have a file call config.php which contains something like this.
<?php
$main="dev.digin.io";
What I need to do is, Whatever the string values which contain after $main= need be replaced with a content in a shell variable like $MainDomain.
Final config.php need to be like this. (consider bash shell variable consist some this like $MainDomain=prod.mail.com )
<?php
$main="prod.mail.com";
This nasty-looking sed substitution gets you what you want:
$ MainDomain=prod.mail.com
$ sed -E "s/^(\\\$main=\")[^\"]+(\";)$/\1$MainDomain\2/" config.php
<?php
$main="prod.mail.com";
Add the -i switch to edit the file "in-place". Use -i.bak to create a backup file config.php.bak.
It looks as though the best thing to do in this situation would be to use a configuration file and adjust your PHP code to read from it, as modifying source code like this is a risky business.
#Daz, could you please try following and let me know if this helps you.
awk -vVAR="$MainDomain" '/\$mainDomain/{sub(/=.*/,"="VAR,$0);} 1' Input_file
Where -vVAR="$MainDomain" VAR is awk's variable which has shell variable named MainDomain's value in it. In awk we can't directly shell variable values so this is how we could assign it to a variable of awk and get it used into it.
Let me know if you have any queries on same.
This question already has answers here:
Editing/Replacing content in multiple files in Unix AIX without opening it
(2 answers)
Closed 6 years ago.
I wonder know if there is a way to edit a conf file without getting in the file and changing the lines?
In my case, I need to edit zabbix-agent conf file (located in /etc/zabbix/zabbix_agentd.conf) and there are some parameters in the file that I need to change, such as Server Name, DebugLevel, and others.
Normally I edit the file using vim and change the lines, but my idea is to edit the file directly from bash, but I don`t know if this is possible.
For example, if I need to change the parameter DebugLevel, at bash I would run:
# /etc/zabbix/zabbix_agentd.conf.DebugLevel=3
This actually doesn`t works, but I would like something like this for my problem...
Does anyone knows??
I tested what David said, but it didn`t solved my problem... There are some lines in the file that is commented and I need to uncomment them, and there are some lines that I just need to change.
For example, the line above:
# DebugLevel=3
I need to change to:
DebugLevel=3
And this line:
Server=127.0.0.1
I need to change for the IP of zabbix server name, like this:
Server=172.217.28.142
Is there any other way?
If I understand your question correctly, then you want sed -i (the -i option allows sed to edit the file in place, and -i.bak will do the same but create a backup of the original file with the .bak extension)
To change DebugLevel=3 to DebugLevel=4 in file /etc/zabbix/zabbix_agentd.conf, you can do:
# sed -i.bak "/DebugLevel/s/[0-9][0-9]*$/4/" /etc/zabbix/zabbix_agentd.conf
If I misinterpreted your question, please let me know.
To Change Values at the End
Example Input File
$ cat file.txt
DebugLevel=3
Example Use
$ sed -i "/DebugLevel/s/[0-9][0-9]*$/4/" file.txt
$ cat file.txt
DebugLevel=4
To Remove Comments
You can do virtually the same thing to uncomment the parameters of interest, for example:
# sed -i.bak "/DebugLevel/s/^#//" /etc/zabbix/zabbix_agentd.conf
In each case, sed is searching for the label in the first set of forward slashes /.../, next the substitute command is called s and then the expression between the next set of forward slashes, e.g. /^#/ (^ match at the beginning), if matched, is replaced by what follows in the next set // (nothing in the remove comment case).
You will need to adjust the values as required to match each parameter you need to find and replace. Let me know if you have further problems and exactly what the problem is.
I have a folder with several files named : something_1001.txt; something_1002.txt; something_1003.txt; etc.
Inside the files there is some text. Of course each file has a different text but the structure is always the same: some lines identified with the string ">TEXT", which are the ones I am interested in.
So my goal is :
for each file in the folder, read the file's name and extract the number between "_" and ".txt"
modify all the lines in this particular file that contain the string ">TEXT" in order to make it ">{NUMBER}_TEXT"
For example : file "something_1001.txt"; change all the lines containing ">TEXT" by ">1001_TEXT"; move on to file "something_1002.txt" change all the lines containing ">TEXT" by ">1002_TEXT"; etc.
Here is the code I wrote so far :
for i in /folder/*.txt
NAME=`echo $i | grep -oP '(?<=something_/).*(?=\.txt)'`
do
sed -i -e 's/>TEXT/>${NAME}_TEXT/g' /folder/something_${NAME}.txt
done
I created a small bash script to run the code but it's not working. There seems to be syntax errors and a loop error, but I can't figure out where.
Any help would be most welcome !
There are two problems here. One is that your loop syntax is wrong; the other is that you are using single quotes around the sed script, which prevents the shell from interpolating your variable.
The grep can be avoided, anyway; the shell has good built-in facilities for extracting the base name of a file.
for i in /folder/*.txt
do
base=${i#/folder/something_}
sed -i -e "s/>TEXT/>${base%.txt}_TEXT/" "$i"
done
The shell's ${var#prefix} and ${var%suffix} variable manipulation facility produces the value of $var with the prefix and suffix trimmed off, respectively.
As an aside, avoid uppercase variable names, because those are reserved for system use, and take care to double-quote any variable whose contents may include shell metacharacters.