$ ifconfig | grep ^en1 -A5 | grep inet | head -n 1
May 12, 2012, 12:30 p.m.
—
Janos
Explanation
This is just for the sake of an example of finding $foo
that occurs after $bar
. Substitute ifconfig
and the arguments of grep
appropriately for your use case.
- In the output of
ifconfig
there are several lines with inet
. We want to get to the first one that comes after a line starting with en1
grep ^en1 -A5
will print the line starting with en1
and the next 5 lines that follow it
grep inet
will print only the lines matching inet
head -n 1
will print only the first line
The value 5 in -A5
is really just a guess that the line we're interested in will be within the next 5 lines, the appropriate number depends on your use case.
Kind of a dumb technique, but it's easy to remember.