Split the content of a string using as delimiter the "=" - linux

Question

How can I split the following output, in order to store the ttl value (64 and 128) into a loop variable?
64 bytes from client2 (192.168.42.5): icmp_seq=1 ttl=64 time=0.324 ms
64 bytes from server (192.168.42.6): icmp_seq=1 ttl=128 time=0.663 ms
Thanks in advance
Regards

Answer 1

The following pipeline is one way to get the specific items you want. The grep extracts only the ttl=something bit and the cut removes the ttl=:
grep -o 'ttl=[^ ]*' | cut -c5-
You can see this in the following transcript:
pax> printf 'AA ttl=64 BB\nCC ttl=128 DD\n'
AA ttl=64 BB
CC ttl=128 DD
pax> printf 'AA ttl=64 BB\nCC ttl=128 DD\n' | grep -o 'ttl=[^ ]*' | cut -c5-
64
128
Or from a real ping command:
:: ping -c 5 127.0.0.1 | grep -o 'ttl=[^ ]*' | cut -c5-
64
64
64
64
64
There are no doubt other pipelines that can do the same thing (perhaps even simpler) but that's the first one that popped into my head. The grep -o flag is quite handy for displaying only the matched text rather than the entire line.
For example, a more complete solution for handling that output may be as follows:
pax> (
...> echo '64 bytes from client2 (192.168.42.5): icmp_seq=1 ttl=64 time=0.324 ms'
...> echo '64 bytes from server (192.168.42.6): icmp_seq=1 ttl=128 time=0.663 ms'
...> ) | awk '
...> / bytes from / {
...> gsub(/ttl=/, "", $7)
...> gsub(/\(/, "", $5)
...> gsub(/\):/, "", $5)
...> print $4" "$5" "$7
...> }' | while read NAME IP TTL ; do
...> echo "Machine ${NAME} with IP ${IP} has TTL ${TTL}"
...> done
Machine client2 with IP 192.168.42.5 has TTL 64
Machine server with IP 192.168.42.6 has TTL 128
The awk first selects the correct records, then modifies the fields so that you don't get the extra stuff (like the ttl= or the parentheses around the IP address). It then prints out three of the fields and sends that through a while loop to process them as single units (one ping response line per unit).
The body of the loop simply outputs the details but you can adjust the behaviour to do something else if desired.

Answer 2

You can use bash regular expressions:
while IFS= read -r line; do
if [[ $line =~ "ttl="([[:digit:]]+) ]]; then
ttl=${BASH_REMATCH[1]}
echo "do something with ttl value $ttl"
fi
done <<END
64 bytes from client2 (192.168.42.5): icmp_seq=1 ttl=64 time=0.324 ms
64 bytes from server (192.168.42.6): icmp_seq=1 ttl=128 time=0.663 ms
END
outputs
do something with ttl value 64
do something with ttl value 128
The BASH_REMATCH array variable contains the text that matched capturing parentheses. Also the 0th index of that array contains the part of the string that matched the whole regex, for example "tty=64" for the first line.

Answer 3

Something like:
stuff | sed -E 's/.*[[:space:]]ttl=([^[:space:]]+).*/\1/'
The regular expression is:
.* match anything
[[:space:]] a single space
ttl= ttl=
([^[:space:]]+) captures a group of one or more non-space characters
.* the rest of the string
Then the end
\1 replaces the whole line with the captured value

Answer 4

Thank you very much for all your answers!!!
I think that is enough to have a fair idea to start.