Get the last column from the output of ls -l
so, with a file/output like this:
drwxrwxr-x 35 user1 www 1536 May 13 2010 dir1 drwxrwxr-x 19 user2 www 512 Sep 28 11:36 dir2 drwxrwxr-x 5 user3 www 1024 Jan 11 2010 dir3 drwxrwxr-x 5 user4 www 398848 Oct 5 2010 dir4 drwxrwxr-x 10 user5 www 512 Feb 23 2012 dir5
sometimes I want to extract the last field. You can dick about with cut(5) etc – but that is quite tedious.
Whilst idly reading the bash man page in the bath, I stumbled across this builtin:
${parameter##word}
Remove matching prefix pattern. The word is expanded to produce
a pattern just as in pathname expansion. If the pattern matches
the beginning of the value of parameter, then the result of the
expansion is the expanded value of parameter with the shortest
matching pattern (the “#'' case) or the longest matching pat-
tern (the “##'' case) deleted. If parameter is @ or *, the
pattern removal operation is applied to each positional parame-
ter in turn, and the expansion is the resultant list. If param-
eter is an array variable subscripted with @ or *, the pattern
removal operation is applied to each member of the array in
turn, and the expansion is the resultant list.
wat ? we need a real world example:
cat /tmp/dirs | while read line ; do echo ${line##*\ } ; done dir1 dir2 dir3
Thats pretty handy !