Problem Set (Raspberry Pi OS):
I have a file example.conf that contains a line IPv4addr=XXXXX. I am attempting to change this to the IP that is generated the in the command
ipTest=$(ip --brief a show | grep eth0 | awk '{ print $3 }')
I want to automate this file change during a script install.sh, the line I am attempting is:
IPtest=$(ip --brief a show | grep eth0 | awk '{ print $3 }')
sudo sed -e "/IPv4addr/s/[^=]*$/$IPtest/" example.conf
Returns error:
sed: -e expression #1, char 32: unknown option to `s'
A simple line in that code works, such as SimpleTest='Works'
Any thoughts? I am open to other solutions as well, however I am not an experienced linux user so I am using the tools I know to work with other problem sets.
$IPtest contains the / character; try something like this:
IPtest=$(ip --brief a show | grep eth0 | awk '{ print $3 }')
sudo sed -e '/IPv4addr/s#[^=]*$#'"$IPtest"'#' example.conf
You can shorten your variable and allow awk to do the job of grep at the same time
IPtest=$(ip --brief a s | awk '/eth0/{print $3}')
Using sed grouping and back referencing
sed -i.bak "s|\([^=]*.\).*|\1$IPtest|" example.conf
Related
I've searched all over and couldn't find a solution.
How would I awk or grep the following:
$ mbimcli -d /dev/cdc-wdm0 -p --query-ip-configuration
[/dev/cdc-wdm0] IPv4 configuration available: 'address, gateway, dns'
IP [0]: '11.22.333.44/55'
Gateway: '14.13.198.4'
DNS [0]: '172.17.1.101'
DNS [1]: '172.17.1.102'
DNS [2]: '172.17.1.101'
DNS [3]: '172.17.1.102'
So that I end up with:
11.22.33.44/55
I've tried a bunch of different combinations with both grep and awk and couldn't find a solution.
Using cat file as I don't have mbimcli -d /dev/cdc-wdm0 -p --query-ip-configuration:
$ cat file | awk -F"'" '/IP \[/{print $2}'
11.22.333.44/55
$ cat file | awk -F"'" '/Gateway/{print $2}'
14.13.198.4
or maybe this is all you need if the output of that command always looks like the example you posted:
$ cat file | awk -v RS= -F"'" '{print $5}'
11.22.333.44/55
$ cat file | awk -v RS= -F"'" '{print $8}'
14.13.198.4
You can do this in a single awk:
mbimcli -d /dev/cdc-wdm0 -p --query-ip-configuration |
awk '$1 == "IP" {gsub(/\047/, "", $NF); print $NF}'
11.22.333.44/55
something like this:
grep '[0-9]' file_with_text | awk '{print $NF}
grep [0-9] only lines with numbers and pipe the output into awk.
The $NF will return the last element.
If you want only the line that has the /, just add it to grep [0-9]/.
Also, for a complete answer, you can pipe the output of the command into grep:
mbimcli -d /dev/cdc-wdm0 -p --query-ip-configuration | grep '[0-9]/' | awk '{print $NF}
I would harness tr for preprocessing and GNU AWK for processing, let file.txt content be
IP [0]: '11.22.333.44/55'
Gateway: '14.13.198.4'
DNS [0]: '172.17.1.101'
DNS [1]: '172.17.1.102'
DNS [2]: '172.17.1.101'
DNS [3]: '172.17.1.102'
then
cat file.txt | tr -d "'" | awk '/IP/{print $NF}'
output
11.22.333.44/55
Explanation: use tr to delete ' then awk to print last column ($NF) if row contain IP.
(tested in tr (GNU coreutils) 8.30 and GNU Awk 5.0.1)
The Xcode console has a 'Debugger output' filter. I understand this is for use with lldb, and that you can get messages to print to this output by using breakpoints. My question is not how to do that.
My question is: what is the underlying mechanism Xcode itself uses to write lldb messages to Debugger Output (not Target Output)? Is there a variable similar to stdout or stderr that writes here? Is it possible, from Xcode target code (Swift/Obj-C/C), to write to this output?
Looks like Xcode uses a tty to communicate with lldb, and you can interface with the Debugger Output using that:
echo "Wheeeeeeee" > $(lsof -p $(ps -A | grep -m1 MacOS/Xcode | awk '{print $1}') | grep -m2 dev/ttys | tail -1 | awk '{print $9}')
Breaking the above down:
$ ps -A | grep -m1 MacOS/Xcode | awk '{print $1}'
21280
This gives the process ID of Xcode (21280). Using this, we can find the files it has open:
$ lsof -p 21280 | grep /dev/ttys
Xcode 21280 tres 47u CHR 16,3 0t0 3569 /dev/ttys003
Xcode 21280 tres 58u CHR 16,5 0t0 3575 /dev/ttys005
The one with the highest number (/dev/ttys005 in this case) is the one we want, so let's extract it. tail -1 will give us the last line of output, and awk '{print $9}' will give us the 9th item on the line, which is what we want!
$ lsof -p 21280 | grep /dev/ttys | tail -1 | awk '{print $9}'
/dev/ttys005
Now we can use this to write whatever we want:
I need to find the ID of some container docker, but some containers have similar names:
$ docker images
REPOSITORY TAG IMAGE ID
app-node latest 620350b79c5a
app-node-temp latest 461c5143a985
If I run:
$ docker images | grep -w app-node-temp | awk -e '{print $3}'
461c5143a985
If I run instead:
$ docker images | grep -w app-node | awk -e '{print $3}'
620350b79c5a
461c5143a985
How can I match the exact name?
I'd say just use awk with exact string matching:
docker images | awk '$1 == "app-node" { print $3 }'
Dashes are considered non-word characters, so grep -w won't work when the difference is marked by a dash.
In context, grep '^app-node[[:space:]]' would work. It looks for the required name followed by a space.
Of course, grep | awk is an anti-pattern most of the time; it would be better to use:
docker images | awk '/^app-node[[:space:]]/ { print $3 }'
Or, an easier solution with awk again uses equality — as suggested by Tom Fenech in his answer:
for server in app-node app-node-temp
do
docker images | awk -v server="$server" '$1 == server { print $3 }'
…
done
If running docker images is too expensive, you can run it once and capture the output in a file and then scan the file. This shows how to pass a shell variable into the awk script.
The chances are the pipeline would be run to capture the container's image ID information:
image_id=$(docker images | awk -v server="$server" '$1 == server { print $3 }')
docker images -q is good for your case
I would like to print the string in the following pattern. And I would like to store it in a array. Please help me, I need O/p as follows
test11
orcl
My commands/Tries
egrep -i ":Y|:N" /etc/oratab | cut -d":" -f1 | grep -v "\#" | grep -v "\*" | tr -d '\n' | sed 's/ /\n/g' | awk '{print $1}'
Above commands O/p:
test11orcl
Contents of Oratab will be as follows,
[oracle#rhel6112 scripts]$ cat/etc/oratab
#
# This file is used by ORACLE utilities. It is created by root.sh
# and updated by the Database Configuration Assistant when creating
# a database.
# A colon, ':', is used as the field terminator. A new line terminates
# the entry. Lines beginning with a pound sign, '#', are comments.
#
# Entries are of the form:
# $ORACLE_SID:$ORACLE_HOME:<N|Y>:
#
# Multiple entries with the same $ORACLE_SID are not allowed.
#
#
test11:/u01/app/oracle/product/11.2.0/dbhome_1:N
orcl:/u01/app/oracle/product/10.2.0/db_1:N
End of Cat Output
From the above file am trying to extract the STRING before the :/
As a start, try this:
$ cat input.txt
test11:/u01/app/oracle/product/11.2.0/dbhome_1:N
orcl:/u01/app/oracle/product/10.2.0/db_1:N
$ awk -F: '{print $1}' input.txt
test11
orcl
update
Using bash:
#!/bin/bash
ARRAY=()
while read -r line
do
[[ "$line" = \#* ]] && continue
data=$(awk -F: '{print $1}' <<< $line)
ARRAY+=($data)
done < input.txt
for i in "${ARRAY[#]}"
do
echo "$i"
done
In action:
$ ./db.sh
test11
orcl
You could use sed also,
sed -r 's/^([^:]*):.*$/\1/g' file
Example:
$ cat cc
test11:/u01/app/oracle/product/11.2.0/dbhome_1:N
orcl:/u01/app/oracle/product/10.2.0/db_1:N
$ sed -r 's/^([^:]*):.*$/\1/g' cc
test11
orcl
OR
$ sed -nr 's/^(.*):\/.*$/\1/p' file
test11
orcl
I am trying to pipe tshark output to awk. The tshark command works fine on its own, and when piped to other programs such as cat, it works fine (real time printing of output). However, when piped to awk, it hangs and nothing happens.
sudo tshark -i eth0 -l -f "tcp" -R 'http.request.method=="GET"' -T fields -e ip.src -e ip.dst -e
tcp.srcport -e tcp.dstport -e tcp.seq -e tcp.ack | awk '{printf("mz -A %s -B %s -tcp \"s=%s sp=%s
dp=%s\"\n", $2, $1, $5, $4, $3)}'
Here is a simplier version:
sudo tshark -i eth0 -f "tcp" -R 'http.request.method=="GET"' | awk '{print $0}'
And to compare, the following works fine (although is not very useful):
sudo tshark -i eth0 -f "tcp" -R 'http.request.method=="GET"' | cat
Thanks in advance.
I had the same problem.
I have found some partial "solutions" that are not completely portable.
Some of them point to use the fflush() or flush() awk functions or -W interactive option
http://mywiki.wooledge.org/BashFAQ/009
I tried both and none works. So awk is not the appropriate command at all.
A few of them suggest to use gawk but it neither does the trick for me.
cut command has the same problem.
My solution: In my case I just needed to put --line-buffered in GREP and not touching awk command but in your case I would try:
sed -u
with the proper regular expression. For example:
sed -u 's_\(.*\) \(.*\) \(.*\) DIFF: \(.*\)_\3 \4_'
This expression gives you the 3rd and 4th columns separate by TAB (written with ctrl+v and TAB combination). With -u option you get unbuffered output and also you have -l option that gives you line buffered output.
I hope you find this answer useful although is late
Per our previous messages in comments, maybe it will work to force closing the input and emitting a linefeed.
sudo tshark -i eth0 -f "tcp" -R 'http.request.method=="GET"' ...... \
| {
awk '{print $0}'
printf "\n"
}
Note, no pipe between awk and printf.
I hope this helps.
I found the solution here https://superuser.com/questions/742238/piping-tail-f-into-awk (by John1024).
It says:
"You don't see it in real time because, for purposes of efficiency, pipes are buffered. tail -f has to fill up the buffer, typically 4 kB, before the output is passed to awk."
The proposed solutions is to use "unbuffer" or "stdbuf -o0" commands to disable buffering. It worked for me like this:
stdbuf -o0 tshark -i ens192 -f "ip" | awk '{print $0}'