Portable way to get file size (in bytes) in shell?

Question

On Linux, I use stat --format="%s" FILE, but Solaris I have access to doesn't have stat command. What should I use then?

I'm writing Bash scripts, and can't really install any new software on the system.

I've considered already using:

perl -e '@x=stat(shift);print $x[7]' FILE

or even:

ls -nl FILE | awk '{print $5}'

But neither of these looks sensible - running Perl just to get file size? Or running 2 commands to do the same?

Answer 1

You first Perl example doesn't look unreasonable to me.

It's for reasons like this that I migrated from writing shell scripts (in bash/sh etc.) to writing all but the most trivial scripts in Perl. I found that I was having to launch Perl for particular requirements, and as I did that more and more, I realised that writing the scripts in Perl was probably a more powerful (in terms of the language and the wide array of libraries available via CPAN) and more efficient way to achieve what I wanted.

Note that other shell-scripting languages (e.g. python/ruby) will no doubt have similar facilities, and you may want to evaluate these for your purposes. I only discuss Perl since that's the language I use and am familiar with.

Answer 2

What about du -s <file> ?

Answer 3

on linux you can use du -h $FILE, does that work on solaris too?

Answer 4

If your find has the necessary capabilities:

size=$( find . -maxdepth 1 -type f -name filename -printf '%s' )

Answer 5

wc -c

Will tell you the number of bytes in a file - hopefully in Solaris too.

I was worried it wouldn't work for binary files, but on my Linux box it worked OK on a .ZIP file.

Answer 6

if you have Perl on your Solaris, then use it. Otherwise, ls with awk is your next best bet, since you don't have stat or your find is not GNU find.

Answer 7

Did you try du -ks | awk '{print $1*1024}'. That might just work.

Answer 8

Finally I decided to use ls, and bash array expansion:

TEMP=( $( ls -ln FILE ) )
SIZE=${TEMP[4]}

it's not really nice, but at least it does only 1 fork+execve, and it doesn't rely on secondary programming language (perl/ruby/python/whatever)

Answer 9

There is a trick in Solaris I have used, if you ask for the size of more than one file it returns just the total size with no names - so include an empty file like /dev/null as the second file:

eg command fileyouwant /dev/null

I can't rememebr which size command this works for ls/wc/etc - unfortunately I don't have a solaris box to test it.