How can I find the Size of some specified files?

Question

The command tries to sum up the sizes:

find . -iname "*.dmg" -exec du -sh '{}' \; 3&> /dev/null |
    awk '{print $1}' | summming_up_program???

Can you find a simpler solution?

Ubuntu Solution. Thanks for the Awk-end to Ayman.

find . -iname "*.dmg" -printf '%b\n' |
    awk 'BEGIN { s = 0 } {s += $1 } END { print "%dMB", s / 2^20 }'

Answer 1

find . -iname '*.dmg' -exec stat -f '%z' '{}' \; |
     awk 'BEGIN { s = 0 } {s += $1 } END { print s }'

stat is used to obtain the size of a file. awk is used to sum all file sizes.

Edit:

A solution that does not fork stat:

find . -iname '*.dmg' -ls | 
     awk 'BEGIN { s = 0 } {s += $7 } END { print s }'

Answer 2

wc -c *.pyc | tail -n1 | cut -f 1 -d ' '

Might be faster then cat'ing the files through the pipe. wc -c does not count the bytes, it retrieves the size from inode... or my hdd has a reading speed of 717 GB/s :-)

$ time wc -c very-big.pcap
5394513291 very-big.pcap
real    0m0.007s
user    0m0.000s
sys     0m0.000s

Answer 3

cat *.dmg | wc -c

cat copies all the files to stdout, and wc counts the size of what was dumped. Nothing gets written to disk.

Not as efficient, but even I can understand it :)

Answer 4

Enhanced Ayman's non-forking command:

find . -iname '*.dmg' -ls 3&> /dev/null | 
      awk 'BEGIN { s = 0 } {s += $7 } END { print "%dGB", s / 2^30 }'

Thanks to Ayman for correcting my initial reply.