Disk usage of files whose names match a regex, in Linux?

Question

So, in many situations I wanted a way to know how much of my disk space is used by what, so I know what to get rid of, convert to another format, store elsewhere (such as da

Answer 1

If you're OK with glob-patterns and you're only interested in the current directory:

stat -c "%s" *.bak | awk '{sum += $1} END {print sum}'

or

sum=0
while read size; do (( sum += size )); done < <(stat -c "%s" *.bak)
echo $sum

The %s directive to stat gives bytes not kilobytes.

If you want to descend into subdirectories, with bash version 4, you can shopt -s globstar and use the pattern **/*.bak