Portable way to get file size (in bytes) in shell?
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
wc -c < filename (short for word count, -c prints the byte count) is a portable, POSIX solution. Only the output format might not be uniform across platforms as some spaces may be prepended (which is the case for Solaris).
Do not omit the input redirection. When the file is passed as an argument, the file name is printed after the byte count.
I was worried it wouldn't work for binary files, but it works OK on both Linux and Solaris. You can try it with wc -c < /usr/bin/wc. Moreover, POSIX utilities are guaranteed to handle binary files, unless specified otherwise explicitly.