For some deployment scripts I want to extract the DB_USER value ('wordpress' in the example) of my wp-config.php file:
define('DB_USER', 'wordpress');
I think sed should be the best tool but I don't find the correct combination.
sed -n "/^ *define( *'DB_USER', *'\([^']*\)'.*/ {s//\1/p;q;}" wp-config.file
in case of absolute use of sed
My suggestion uses awk:
grep DB_USER wp-config | awk -F\' '{print $4}'
Related
I already know that sed uses own approach to deal with single quote but I think it still possible to use it in my automation script.
I had to replace value of fingerprint in Saltstack config file.
Current value:
#master_finger: ''
Target value
master_finger: 'some:value'
My current command which doesn't work:
$ sed -i 's/#master_finger: ''/master_finger: 'some:value'/g' /etc/salt/minion
returns:
master_finger: some:value''
How can I solve this?
just use the double quotes to enclose the script.
$ echo "#master_finger: ''" | sed "s/#master_finger: ''/master_finger: 'some:value'/"
master_finger: 'some:value'
It's not sed that's making handling of 's difficult, it's the shell because the shell does not allow 's within any '-quoted string, including scripts.
You could save the sed script in a file and run it with -f or use a here document:
$ sed -f- file <<'EOF'
s/#master_finger: ''/master_finger: 'some:value'/g
EOF
master_finger: 'some:value'
To see the difference between the above and #karakfas suggestion:
$ sed -f- file <<'EOF'
s/#master_finger: ''/master_finger: '$(date)'/g
EOF
master_finger: '$(date)'
$ sed "s/#master_finger: ''/master_finger: '$(date)'/" file
master_finger: 'Sun Feb 14 06:50:43 CST 2021'
and imagine if date was replace by rm -rf * or something worse.
Also consider:
$ sed 's/#master_finger: '\'\''/master_finger: '\''$(date)'\''/' file
master_finger: '$(date)'
I a file containing the genome ids following NZ_FLAT01000030.1_173 I need to manipulate those ids like this one: NZ_FLAT01000030.1
I tried some but didn't give me the exact thing.
sed 's/_/\t/' output : NZ FLAT01000030.1_173
sed -r 's/_//' output: NZFLAT01000030.1_173
sed -r 's/_//g' output: NZFLAT01000030.1173
How can I do that by using sed command?
Are you trying to remove the undesrscore and the digits following it?
echo 'NZ_FLAT01000030.1_173' | sed -E 's/_[0-9]+//g'
NZ_FLAT01000030.1
$ echo 'NZ_FLAT01000030.1_173' | sed 's/_[^_]*$//'
NZ_FLAT01000030.1
I have the following sed command:
sed -i -E "s/\{\{(.*)\}\}/$(echo "$\1")/g" test.conf
In test.conf, I have this:
this is a {{TEST}}
and this is an {{ANSWER}} here.
And I have the follow environment variables set:
export TEST=1234
export ANSWER=5678
When I run the sed command, I end up with this result:
this is a $TEST
and this is an $ANSWER here.
I want 1234 and 5678 there respectively. Is there a reason the echo command is interpreting things literally?
Backreferences are used internally by a single sed command. The echo has no idea about sed backreferences and would have been invoked by the shell before the sed command has even run so the $(echo "$\1") is outputing $\1 so
sed -i -E "s/\{\{(.*)\}\}/$(echo "$\1")/g" test.conf
is really:
sed -i -E "s/\{\{(.*)\}\}/$\1/g" test.conf
hence the output you are seeing.
Anyway, sed is for simple subsitutions on individual lines, for anything else you should be using awk:
$ export TEST=1234 ANSWER=5678
$ awk 'match($0,/(.*)\{\{(.*)\}\}(.*)/,a){$0=a[1] ENVIRON[a[2]] a[3]} 1' file
this is a 1234
and this is an 5678 here.
The above uses GNU awk for the 3rd arg to match(), with other awks it'd be:
$ awk 'match($0,/\{\{(.*)\}\}/){$0=substr($0,1,RSTART-1) ENVIRON[substr($0,RSTART+2,RLENGTH-4)] substr($0,RSTART+RLENGTH)} 1' file
this is a 1234
and this is an 5678 here.
If anyone suggests running eval or similar on the sed output - don't do it (google eval is evil and friends), just use the awk command above for simple string operations.
You can use perl which conveniently has a %ENV hash variable, see perldoc for more info
perl -pe 's/\{\{(.*)\}\}/$ENV{$1}/' test.conf
I have the following sed command. I need to execute the below command in single line
cat File | sed -n '
/NetworkName/ {
N
/\n.*ims3/ p
}' | sed -n 1p | awk -F"=" '{print $2}'
I need to execute the above command in single line. can anyone please help.
Assume that the contents of the File is
System.DomainName=shayam
System.Addresses=Fr6
System.Trusted=Yes
System.Infrastructure=No
System.NetworkName=AS
System.DomainName=ims5.com
System.DomainName=Ram
System.Addresses=Fr9
System.Trusted=Yes
System.Infrastructure=No
System.NetworkName=Peer
System.DomainName=ims7.com
System.DomainName=mani
System.Addresses=Hello
System.Trusted=Yes
System.Infrastructure=No
System.NetworkName=Peer
System.DomainName=ims3.com
And after executing the command you will get only peer as the output. Can anyone please help me out?
You can use a single nawk command. And you can lost the useless cat
nawk -F"=" '/NetworkName/{n=$2;getline;if($2~/ims3/){print n} }' file
You can use sed as well as proposed by others, but i prefer less regex and less clutter.
The above save the value of the network name to "n". Then, get the next line and check the 2nd field against "ims3". If matched, then print the value of "n".
Put that code in a separate .sh file, and run it as your single-line command.
cat File | sed -n '/NetworkName/ { N; /\n.*ims3/ p }' | sed -n 1p | awk -F"=" '{print $2}'
Assuming that you want the network name for the domain ims3, this command line works without sed:
grep -B 1 ims3 File | head -n 1 | awk -F"=" '{print $2}'
So, you want the network name where the domain name on the following line includes 'ims3', and not the one where the following line includes 'ims7' (even though the network names in the example are the same).
sed -n '/NetworkName/{N;/ims3/{s/.*NetworkName=\(.*\)\n.*/\1/p;};}' File
This avoids abuse of felines, too (not to mention reducing the number of commands executed).
Tested on MacOS X 10.6.4, but there's no reason to think it won't work elsewhere too.
However, empirical evidence shows that Solaris sed is different from MacOS sed. It can all be done in one sed command, but it needs three lines:
sed -n '/NetworkName/{N
/ims3/{s/.*NetworkName=\(.*\)\n.*/\1/p;}
}' File
Tested on Solaris 10.
You just need to put -e pretty much everywhere you'd break the command at a newline or have a semicolon. You don't need the extra call to sed or awk or cat.
sed -n -e '/NetworkName/ {' -e 'N' -e '/\n.*ims3/ s/[^\n]*=\(.*\).*/\1/P' -e '}' File
My script takes a file name in the form R#TYPE.TXT (# is a number and TYPE is two or three characters).
I want my script to give me TYPE. What should I do to get it? Guess I need to use awk and sed.
I'm using /bin/sh (which is a requirement)
you can use awk
$ echo R1CcC.TXT | awk '{sub(/.*[0-9]/,"");sub(".TXT","")}{print}'
CcC
or
$ echo R1CcC.TXT | awk '{gsub(/.*[0-9]|\.TXT$/,"");print}'
CcC
and if sed is really what you want
$ echo R9XXX.TXT | sed 's/R[0-9]\(.*\)\.TXT/\1/'
XXX
I think this is what you are looking for.
$ echo R3cf.txt | sed "s/.[0-9]\(.*\)\..*/\1/"
cf
If txt is always upper case and the filename always starts with R you could do something like.
$ echo R3cf.txt | sed "s/R[0-9]\(.*\)\.TXT/\1/"
You can use just the shell (depending what shell your bin/sh is:
f=R9ABC.TXT
f="${f%.TXT}" # remove the extension
type="${f#R[0-9]}" # remove the first bit
echo "$type" # ==> ABC