Get the last 4 characters of output from standard out

Question

I have a script that is running and uses

lspci -s 0a.00.1 

This returns

0a.00.1 usb controller some text device 4dc9


        

Answer 1

How about tail, with the -c switch. For example, to get the last 4 characters of "hello":

echo "hello" | tail -c 5
ello

Note that I used 5 (4+1) because a newline character is added by echo. As suggested by Brad Koch below, use echo -n to prevent the newline character from being added.

Answer 2

If the real request is to copy the last space-separated string regardless of its length, then the best solution seems to be using ... | awk '{print $NF}' as given by @Johnsyweb. But if this is indeed about copying a fixed number of characters from the end of a string, then there is a bash-specific solution without the need to invoke any further subprocess by piping:

$ test="1234567890"; echo "${test: -4}"
7890
$

Please note that the space between colon and minus character is essential, as without it the full string will be delivered:

$ test="1234567890"; echo "${test:-4}"
1234567890
$

Answer 3

instead of using named variables, develop the practice of using the positional parameters, like this:

set -- $( lspci -s 0a.00.1 );   # then the bash string usage:
echo ${1:(-4)}                  # has the advantage of allowing N PP's to be set, eg:

set -- $(ls *.txt)
echo $4                         # prints the 4th txt file.