Nsryjdtyk

I want to add and echo the sum of several files using shell script. How do I start?
I have a list of them like that:

$ stat /etc/*.conf | grep Size | cut -f4 -d' '

123

456

789

101112

You can do this …

total=0

for s in $(stat /etc/*.conf | grep Size | cut -f4 -d' '); do 

    total=$(expr $total + $s)

done

stat -c "%s" /etc/*.conf|paste -sd+|bc -l

Also something like can do the work (with awk)

stat -c "%s" /etc/*.conf|awk '{s+=$1} END {print s}'

With bc

{ stat -c '%s+' /etc/*.conf ; echo 0 ; } | bc

• The stat format adds a + sign and a continuation character after each size


• a 0 is appended at the end to close the dangling final +
  

The most straightforward way is to use du -bc:

$ du -bc /etc/*.conf

5139    /etc/man_db.conf

393     /etc/nsswitch.conf

5532    total

If you need to extract only the number of bytes, pipe the output to awk:

$ du -bc /etc/*.conf | awk 'END { print $1 }'

5532

The easiest way to sum numbers from a shell is using num-utils, which is available as a package in Debian-based distros such as Ubuntu. Simply pipe the output into numsum.

Example:

$ printf "%dn" 1 2 3 | numsum

6

The package contains a bunch of other useful numeric utils as well. Quoting from the project page:

The 'num-utils' are a set of programs for dealing with numbers from the Unix command line. Much like the other Unix command line utilities like grep, awk, sort, cut, etc. these utilities work on data from both standard in and data from files.

• numaverage: A program for calculating the average of numbers.


• numbound: Finds the boundary numbers (min and max) of input.


• numinterval: Shows the numeric intervals between each number in a sequence.


• numnormalize: Normalizes a set of numbers between 0 and 1 by default.


• numgrep: Like normal grep, but for sets of numbers.


• numprocess: Do mathematical operations on numbers.


• numsum: Add up all the numbers.


• numrandom: Generate a random number from a given expression.


• numrange: Generate a set of numbers in a range expression.


• numround: Round each number according to its value.