Shell Programming and Scripting

$home> vi abcd.txt
/a/b/c/r1.txt
/q/w/e/r2.txt
/z/x/c/r3.txt

/a/b/c/
/q/w/e/

while read file
do
  cd  <here need the directory path for each row>
  .. do some common operation ...
done < abcd.txt

"${file##*/}"

while read file
do
  dir = `dirname $file`
  print $dir
done < latest.txt

$ for F in /a/b/c/r1.txt /q/w/e/r2.txt /z/x/c/r3.txt; do echo ${F%/*}/; done
/a/b/c/
/q/w/e/
/z/x/c/

for file in "/a/b/c/r1.txt" "/q/w/e/r2.txt" "/z/x/c/r3.txt"
do
        echo "${file%%${file##*/}}"
done

/a/b/c/
/q/w/e/
/z/x/c/

$ ruby -ne 'puts File.dirname($_)' file
/a/b/c
/q/w/e
/z/x/c