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 $3 }')
docker images -q is good for your case
Related
Problem Set (Raspberry Pi OS):
I have a file example.conf that contains a line IPv4addr=XXXXX. I am attempting to change this to the IP that is generated the in the command
ipTest=$(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
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)
I'm writing a shell script which shut down some services and trying to get its pid by using the following awk script.
However, this awk script can't get pid. What's wrong with that?
ps -ef | awk -v port_no=10080 '/[m]ilk.*port=port_no/{print $2}'
The result of ps -ef is like this:
username 13155 27705 0 16:06 pts/2 00:00:00 /home/username/.rbenv/versions/2.3.6/bin/ruby /home/username/.rbenv/versions/2.3.6/bin/milk web --no-browser --host=example.com --port=10080
This process is working with a different port argument as well, so I want to kill the process only working on port=10080.
The awk script below works fine, but when I specify the port no using awk -v like the above, it doesn't work well.
ps -ef | awk '/[m]ilk.*port=10080/{print $2}'
awk version: GNU Awk 4.0.2
The syntax for pattern matching with /../ does not work with variables in the regular expression. You need to use the ~ syntax for it.
awk -v port_no=10080 '$0 ~ "[m]ilk.*port="port_no{print $2}'
If you notice the regex carefully, the regex string on the r.h.s of ~ is under the double-quotes ".." except the variable name holding the port number which shouldn't be under quotes, for the expansion to happen.
This task is easily accomplished using pgrep:
$ pgrep -f '[m]ilk.*port=10080'
Have a look at man pgrep for details.
Friends,
I'm trying to extract the last part of following path in a ksh script:
TOOL_HOME=/export/fapps/mytool/mytool-V2-3-4
I want to extract the version # (i.e., 2-3-4) from the above.
awk runs fine on SuSE:
echo $TOOL_HOME | awk -F'mytool-V' '{print $2}'
#2-3-4
However, on Solaris 10, it produces the following:
#ytool
So on Solaris, awk is ignoring everything after the first character in -F'mytool-V'
What should i do to get the same output on both OS's?
On Solaris use /usr/xpg4/bin/awk, not /bin/awk (aka "old, broken awk").
Solaris awk is broken...
$ echo "$TOOL_HOME" | awk '{sub(/.*mytool-V/,"")}1'
2-3-4
or simply with sed
$ echo "$TOOL_HOME" | sed 's/.*mytool-V//'
2-3-4
No need to use awk or any other external program. ksh can do that:
echo ${TOOL_HOME##*mytool-V}
I am running the following command using awk on file.txt ,currently its running the command on the ids present in file.txt from top to bottom..i want the commmand to be run in the reverse order for the ids present in file.txt..any inputs on how we can do this?
git command $(awk '{print $1}' file.txt)
file.txt contains.
97a65fd1d1b3b8055edef75e060738fed8b31d3
fb8df67ceff40b4fc078ced31110d7a42e407f16
a0631ce8a9a10391ac4dc377cd79d1adf1f3f3e2
.....
If you aren't bound to using awk then tail with the -r (for reverse) argument will do the trick...
myFile.txt
97a65fd1d1b3b8055edef75e060738fed8b31d3
fb8df67ceff40b4fc078ced31110d7a42e407f16
a0631ce8a9a10391ac4dc377cd79d1adf1f3f3e2
Now to print it in reverse...
$ tail -r myFile.txt
a0631ce8a9a10391ac4dc377cd79d1adf1f3f3e2
fb8df67ceff40b4fc078ced31110d7a42e407f16
97a65fd1d1b3b8055edef75e060738fed8b31d3
EDIT:
To output this to a file simply redirect it out...
$ tail -r myFile.txt > newFile.txt
EDIT:
Want to write to the same file? No problem!
tail -r myFile.txt > temp.txt; cat temp.txt > myFile.txt; rm temp.txt;
For some reason when I redirected tail -r to the same file it came back blank, this workaround avoids that issue by writing to a temporary "buffer" file.
To reverse the lines in a file using awk, use
awk '{a[i++]=$0} END {for (j=i-1; j>=0;) print a[j--] }' file
use $1 instead of $0 above to operate on the first field only instead of the whole line.